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July 31, 2006
"Chris died for your sins."
Well, the Agonist is up to Israeli-Hezbollah Conflict Open Thread VIII...
There are now eggs that show you when they're boiled with magically-appearing ink on the shell.
New Image Plants makes the the silk-leaf fauxijuana for Showtime's series Weeds and also sells them retail online. via
How-to: DJ your first set without knowing how via
Every piece of Rocket Chocolate is dosed with a hefty 150mg of caffeine. via
Posted by Jon Rubin at 09:10 PM | Comments (0) | TrackBack
July 30, 2006
"OK, I want channels 18, 24, 63, 109, 87 and the Weather Channel."
So to tear myself away from my LCD for a minute...
If you want to attach a Mac to a Westinghouse LVM-37w3 via DVI, you have to download SwitchResX. Well, you don't have to. It's just, if you don't, OS X feeds the panel a 1080i signal instead of a progressive one.
I think my favorite 1080p sample movie is the Cornell Macaulay Library Ornithology video over at the Apple QuickTime HD Gallery.
And, um...that's it. I'm sure my optic nerves will desensitize in a few days and the HDTV will lose its mesmerizing power...right?
Posted by Jon Rubin at 10:27 PM | Comments (0) | TrackBack
July 29, 2006
Oh my god it's full of pixels!
No real post tonight, as my day was spent purchasing a very well-regarded new TV, the Westinghouse LVM-37w3.
Sooooooooooooooooooooooooooooooooooooooooooooooooo
Prettttttttttttttttttttttttttttttttttttttttttttttttttttty
!!!!!!!!!!!!!!!!!!!!!!!!!!!!
My last monitor was a 17" Radius CRT with a 1024x768 resolution.
My last television was a standard definition 20" Sony CRT so old it lacked S-Video inputs, let alone component.
This new gem of an LCD panel is 37" and has a 1920x1080 resolution. That's right: 1080p, baby!
The most surprising thing is how well it works with the legacy interfaces. I don't have any DVI or component cables around, so I'm feeding it from a cable box over composite, a DVD player over S-Video, and my G5 PowerMac over VGA. Even with an analog connection, it works perfectly at its full rez. And the DVD player! It looks waaaaaay better than I expected it would. It scales to full screen with just the slightest blurriness, and I'm not even pushing it a progressive signal yet, so it's deinterlacing as well!
Speaking of scaling, I threw a 720p copy of The 5th Element at the display, and it looked so good my dad thought it was full HD.
The backlight is so strong it might transform the term "monitor tan" from irony to reality.
I installed Synergy, so I just move my laptop's cursor above its menu bar and Whooosh! I'm controlled the flat panel. VNC was struggling with the resolution.
I'd held off on buying the Westy for months; it's near impossible to find them in stores in the Tampa Bay area and I was hesitant to buy before viewing it in action. Today, Best Buy showed one in stock at Tyrone Mall, and I snatched it up sight-unseen.
Had I anticipated just how sublime the set would be, I'd have plunked down the cash long ago.
Posted by Jon Rubin at 09:38 PM | Comments (0) | TrackBack
July 28, 2006
"And as every present state of a simple substance is naturally a consequence of its preceding state, so its present is pregnant with its future."
More help for the lazy sci-fi author: space weapons (or: sp'weapons). via
Powering up a particle beam to the point where it can cut armor is difficult. But there is another option: death by "Bremsstrahlung".
Consider the the x-ray tube in your dentist's office. It is basically an electron beam striking a metal target. Now, what if the electron beam was a particle beam weapon and the metal target was the hull of the enemy spacecraft? A hypothetical observer on the far side of the ship could make a nifty x-ray photo revealing the skeletons of crew members dying in agony of radiation poisoning.
Please note that Bremsstrahlung only occurs with charged particle beams, it doesn't happen with beams of neutrons.
Of course the simplest is no warhead at all, making the structure of the missile an impromptu kinetic kill weapon. According to the first law of space combat, above about a three km/s relative velocity difference a chemical explosive warhead is superfluous. Rick Robinson says that at these speeds the only reason for conventional explosives is for the bursting charge on a shrapnel cloud.
I know all you Battlestar Galactica fans are not going to want to hear it, but looking from a cost/benefit analysis, space fighter craft do not make any sense. Go to The Tough Guide to the Known Galaxy and read the entry "SPACE FIGHTERS"
Rick Robinson said: "Fighters substantially outperforming big ships can be justified, though. Big ships (presumably) need crew habitability for extended voyages, fuel for same, usually an FTL gizmo, and crew including maintenance types, etc. All of which are mass penalties. A fighter is pretty much just drive engine, enough delta v for its mission profile, minimal habitability for a minimal crew, and ordnance carried."
Being a spoil-sport, I said: "The question then becomes why doesn't the designers replace the minimal habitability crew space with some electronics and turn the fighter into a missile bus."
Mr. Robinson answered with: "What a rude question. {grin}". But then he got me, by invoking Burnside's Zeroth Law of Space Combat. SF fans don't want to read about the life and times of a nuclear missile, therefore space fighters will exist.
The spoilerrific Top 50 Movie Endings of All Time (endings, as in final minutes, not final act twists) won my heart by putting Real Genius smack dab in the center. via
Tim Boucher's been researching the occult's relationship with science lately. It's a topic that's been on my mind since reading Neal Stephenson's Baroque Cycle this past spring. The overarching theme of that series of novels is that outmoded belief systems do not disappear or die out, but, rather, remain as the hidden (occulted) foundation of new conceptual models. When apocalypses occur, what was before is not destroyed but reborn. Chemistry didn't replace alchemy as much as the former subsumed the latter, as Christ superceded Mithras, as bankers developed from goldsmiths. There's no firm dividing line between epochs. The Royal Society counted alchemists amongst its members from the beginning. As Tim discovered, the RS then moved on to fraternizing with the Freemasons, as they had similar conflicts with the Powers That Be:
We’ve already seen that by championing scientific exploration and discourse in their lodges while it was outlawed most everywhere, the Freemasons must have aroused the ire of the Church. This was, you may recall, only a little over 25 years after the Catholic Church had Galileo tried for heresy for publishing scientific ideas counter to the Bible. With such a clear division between religious authority and what the Masons were doing, it is small wonder that they were painted by Luciferians by the Church, and also seemed to have proudly adopted that symbol of rebellion in some cases of their own accord. The use of Lucifer for them - if you take their talk of dismantling superstition and outmoded religious authorities at face value - worked in their minds as a secular-literary symbol, while for Christians it retained the much more loaded “superstitious” meaning of devil-worship.
This talk too of “destroying the moral and social order” makes sense when you realize the “moral and social order” in question is the authority of Churches everywhere. There is a good Adam Weishaupt quotes about something similar, such as “When man lives under government, he is fallen, his worth is gone, and his nature tarnished.”
Anyway, Tim's now gone a bit further and discovered some fascinating information about the technocrats. Before the term was transformed into a slur lobbed at Dukakis-style liberals, technocracy was a sophisticated ideological movement. They intend to provide societal structure after the collapse of the capitalist nation-state by migrating to a true energy economy.
As near as I can tell, sci-fi author H.G. Wells popularized the term “Technocracy” in his book The Shape of Things to Come. It is essentially a “government by experts,” or more broadly “a government or organizational system where decision makers are usually highly-skilled in fields of management or any other field.”
The term “technocracy” is also referenced in James Burnham’s 1940 book, The Managerial Revolution. I found an essay by none other George Orwell which seems to summarize Burnham’s book.
Orwell in that essay seems to be saying the Burnham believes Nazi Germany and the USSR to be examples of this new “managerial” model of society. That description Orwell gives above though of course sounds like a plot outline for his novel 1984. I am assuming that Orwell penned this essay around the time when Burnham’s book came out, because he is analyzing predictions for the course of the war that Burnham makes, and 1984 (originally titled The Last Man In Europe) wasn’t published until 1948. Burnham’s book is also listed under Orwell’s influences for that novel.
The technocratic movement in the United States was originally begun by Howard Scott, who created the Technical Alliance after World War I, which was one of the nation’s first think tanks. They did some kind of “energy survey” of North America, which I frankly don’t understand and then were disbanded. According to Wikipedia, “In 1933, the group became incorporated in the state of New York as a non-profit, non-political, non-sectarian organization known as Technocracy Incorporated.” And they still exist under that name, Technocracy, Inc. today.
That ying-yang looking thing is what they refer to as their “monad” whose meaning is said to be something like “a balance between a nation’s production and consumption” - presumably through perfect technical-scientific control.
One of the most interesting things I have found is that apparently Peak Oil theory (aka Hubbert Peak Theory) - which has been on everyone’s lips a lot the past couple years - was created by a member of Technocracy, Inc, M. King Hubbert. If that doesn’t interest you, then perhaps mention of their hopes and aspirations will. Seems they want to create something called the North American Technate to replace the current nationalist system in place today.
In my opinion, the next step for Mr. Boucher should probably be a thorough investigation of the Fabian Society, which was founded by Wells and counted Orwell as a member...
Sidenote: for once my title quote is appropriate for every item! The sci-fi weapons are extrapolations of the "present state" of weapons technology, Real Genius' ending is "naturally a consequence" of an off-hand statement early in the movie and literally grows out of a kernel, the theme of the Baroque Cycle is a rephrasing of the very Leibniz quote I chose as the title, the technocrats use Leibniz' monad as their logo (my title quote is from Monadology), and the Fabians pretty much invented the modern notion of progress and adopted gradual evolution as their favored method of action.
Posted by Jon Rubin at 06:34 PM | Comments (0) | TrackBack
July 27, 2006
"Remember the spider that lived outside your window? Orange body, green legs. Watched her build a web all summer, then one day there's a big egg in it. The egg hatched..." "The egg hatched..." "Yea." "And a hundred baby spiders came out and they ate her."
The iLiad is the first usable ebook reader. It's pretty much Sony's Librie device, sans DRM.
Apple's now the #4 computer maker, and its laptop market share is up to 12%.
During World War II, statistics worked better than human intelligence for figuring out how many tanks the Nazis were producing. via
The statisticians had one key piece of information, which was the serial numbers on captured mark V tanks. The statisticians believed that the Germans, being Germans, had logically numbered their tanks in the order in which they were produced. And this deduction turned out to be right. It was enough to enable them to make an estimate of the total number of tanks that had been produced up to any given moment.
By using this formula, statisticians reportedly estimated that the Germans produced 246 tanks per month between June 1940 and September 1942. At that time, standard intelligence estimates had believed the number was far, far higher, at around 1,400. After the war, the allies captured German production records, showing that the true number of tanks produced in those three years was 245 per month, almost exactly what the statisticians had calculated, and less than one fifth of what standard intelligence had thought likely.
Emboldened, the allies attacked the western front in 1944 and overcame the Panzers on their way to Berlin.
Neil Armstrong's sleepless night on the Moon was commemorated recently.
Armstrong was particularly fascinated by moondust, which he kicked and scuffed with his boots. On Earth, kicking dust makes a little cloud in the air--but there is no air on the Moon. "When you kick the surface, [the dust goes out in] a little fan which, to me, is in the shape of a rose petal," recalls Armstrong. "There's just a little ring of particles--nothing behind 'em--no dust, no swirl, no nothing. It's really unique."
Seems that implanted memories can condition aversion reactions. via
Participants' memories were manipulated by telling them that a computer had generated a personal profile based on a questionnaire about past eating and drinking habits. They were told they had become sick on rum in the past and they were asked to elaborate on that experience.
About a quarter of the participants became more confident they had actually been sick on rum. "Between 30 and 40% increased their confidence for the item in comparison to a control group," he says. When asked to rate how much they liked rum they rated it less than before their memories were manipulated.
But prior bad experiences don't create an aversion to all foods and drinks, only those with a distinct or unusual flavour.
"With some drinks and some food you may have got sick but it doesn't seem to have this imprint, this lasting effect," he says.
He said his previous research managed to induce an aversion to strawberry ice cream, but didn't work when it came to chips. "We couldn't turn them off potato chips, we got a little rebound and they thought 'give me more!'"
The optic nerve has the same bandwidth as Ethernet, 10 megabits per second. via
The guinea pig retina was placed in a dish and then presented with movies containing four types of biological motion, for example a salamander swimming in a tank to represent an object-motion stimulus. After recording electrical spikes on an array of electrodes, the researchers classified each cell into one of two broad classes: "brisk" or "sluggish," so named because of their speed.
The researchers found that the electrical spike patterns differed between cell types. For example, the larger, brisk cells fired many spikes per second and their response was highly reproducible. In contrast, the smaller, sluggish cells fired fewer spikes per second and their responses were less reproducible.
But, what's the relationship between these spikes and information being sent? "It's the combinations and patterns of spikes that are sending the information. The patterns have various meanings," says co-author Vijay Balasubramanian, PhD, Professor of Physics at Penn. "We quantify the patterns and work out how much information they convey, measured in bits per second."
Calculating the proportions of each cell type in the retina, the team estimated that about 100,000 guinea pig ganglion cells transmit about 875,000 bits of information per second. Because sluggish cells are more numerous, they account for most of the information. With about 1,000,000 ganglion cells, the human retina would transmit data at roughly the rate of an Ethernet connection, or 10 million bits per second.
Printing on water using standing cylindrical waves as pixels. It looks like the bastard spawn of a ménage à trois among a typewriter, a kiddie pool, and the Stargate.
Posted by Jon Rubin at 09:28 PM | Comments (0) | TrackBack
July 26, 2006
"Coffee, (which makes the politician wise, / And see thro’ all things with his half-shut eyes)."
My parents tasked me with finding a good coffee maker, which proved to be a Learning Experience.
For example, an Ask MetaFilter question about hot drip coffee makers taught me that most coffee makers suck.
See, according to the Specialty Coffee Association of America, you want your water to be around 185-200 degrees Fahrenheit before it hits the ground coffee. Most coffee makers never get the water that hot. The coffee geeks' intensity on this matter knows no bounds:
I don't have a lot of respect for auto drip coffee makers.
It's not because I don't like the taste of the coffee that auto drips are capable of making. I don't like these machines in general because they are underpowered. Most appliance manufacturers manage to limit the top brewing temperatures of the water in auto drip coffee makers, either on purpose (fear of lawsuits from people who manage to spill 180F + coffee on themselves) or through poor product design and poor parts quality.
Poor product design is reflected in the tendancy for many auto drip coffee brewers to use the same heat source for water as they do for the hot plate under the carafe. That's right - in many cases, water is flash heated as it passed through the exact same heating coil/device that is used to keep the pot warmer hot. Problem is, to adequately heat up that water to proper brewing temperatures, the hot plate would be too hot for the carafe, so they dial down the heat. Your brew suffers.
What's even more scary is the "company line" followed by some appliance makers. I had the head technical troubleshooter at Saeco USA once tell me that coffee is "supposed to be brewed at 165F" when he was contacted about complaints that the Saeco Latte was brewing too cold. And once, I wrote Braun enquiring why their machines never seem to produce temperatures hotter than 180F at the showerhead (in the carafe, the coffee is closer to 175F), and they told me that their extensive scientific study has "proven" that 175F to 180F is the optimum brewing temperatures.
Folks, they are fooling themselves. For over a century now, coffee experts have known that for gravity filter drip coffee, 190 to 200F is the general range, and 192-197F is the sweetspot range for proper extraction (sources: Ukers, All About Coffee (1935) to Specialty Coffee Association of America, current day). Don't settle for anything less.
The best drip coffee maker that gets water hot enough is made by crafty Dutchmen and has the impressive name of Technivorm. It costs around $200 bucks, tho.
I also found a great review of Nissan's Thermos product line. I think I'm going to order a TGS1000 NSF-certified restaurant-grade coffee carafe (the TGS1000 keeps things hot forever) and a JCA350 12oz soda/beer can insulator. And maybe a JMQ400C leak-proof travel mug too (the JMQ400C really is leak-proof and well-insulated). Perhaps a JMW500 leakproof backpack bottle as well?
I'm a sucker for liquid containers. The last time I got near Nalgene's online store I ended up with two 32oz bottles, a 48-oz canteen, a flask, two different 16oz bottles, a dropper bottle, and a set of various smaller vessels...
The Krups Moka Brew also looks interesting, with its whole pressure-based system, but it seems a little complicated for my parents...
I'm not hard-core enough to go for a vacuum brewer or a french press.
Posted by Jon Rubin at 10:19 PM | Comments (0) | TrackBack
July 25, 2006
"Over a billion years, we foolish molecules forget who we are and where we came from. In desparate acts of ego, we give ourselves names, fight over lines on maps, and pretend that our light is better than everyone else's."
Complexity visualized. Pretty pretty graphics. I like the "perfectly balanced" tree's fractal spirals... via
For the lazy sci-fi author, 3D star maps. via
"Hard" SF writers and interstellar game designers need reasonably accurate 3-D starmaps in order to set the stage. This webpage is a feeble attempt to assist those who lack the knowledge (or inclination) to do the work themselves. You don't have any excuse now, I've done most of the work for you! If nothing else, grab the maps!
Via that last link, an obsessively complete investigation into the location of Babylon 5 and the astrographical extent of the Shadow War in the Milky Way galaxy.
So, does this settle the issue? Well, there are still problems.
We have seen in several shows – most notably in Interludes and Examinations – that Babylon 5 and Epsilon 3 orbit a star which is yellow-white in appearance. Indeed, the star looks a whole lot like our sun.
Epsilon Eridani is a K2 star, basically orange to orange-red in color. Like our sun, if one looked directly at it, the star would appear white, but it would have an orangish corona. The star we've seen in the show is white with a yellow-white corona.
Bob Donahue points out that Epsilon Eridani is only about one billion years old, and thus probably too young for interesting life to have evolved. So far, this isn't a problem – there's no reason to believe that any of the races we've seen in the Great Machine on Epsilon 3 are native to the planet.
Epsilon Eridani is 10.67 light-years from the earth (according to the 1991 Gliese list; see appendix for sources). This is certainly much closer than the 25 or 35 light-years mentioned earlier. It also contradicts some more recent data: in Face of the Enemy, Lise Hampton Edgars tells Garibaldi that she didn't want a relationship with someone who was "18 light-years away". Of course, she may simply have forgotten B5's true distance in her annoyance with Garibaldi.
So we seem to have a few possible options:
• We can accept that Babylon 5 is in the Epsilon Eridani system. It seems odd that the newscaster would refer to this as the Epsilon Eridani "sector", and we have to assume that the star's color is not shown correctly. Nearly all stars in the show are shown as "yellow"; this may simply be artistic license (like sound in space, or the fact that space in Babylon 5 seems more often blue or purple than it is black.
• Perhaps B5 is in the "Epsilon Eridani Sector", a huge region of space. This seems odd, since Epsilon Eridani is fairly insignificant as stars go; it seems odd to name a "sector" after it.
• Perhaps sectors are small. Then B5 is very close to Epsilon Eridani. There are only two star-systems under six light-years from E Eridani:
One is Tau Ceti, 5.3 light-years from Epsilon Eridani, and 11.40 LY from Earth. It is G8 (yellow or orange-yellow). This would be a good candidate. But Tau Ceti is as bright, as close, and as well-known as E Eridani. Why not refer to it by name, instead of assigning it to E Eridani's "sector"?
The other is UV Ceti, 5.2 LY from Epsilon Eridani, and 8.57 LY from Earth. The UV Ceti system contains a pair of M5 red dwarfs. But there are at least two problems here: UV Ceti is only 2.9 LY from Tau Ceti – so shouldn't it be in the "Tau Ceti sector"? The other is that red dwarfs are small, cold, and don't look like the star we see on TV.
There could be an undiscovered star a few light-years past Epsilon Eridani. Seriously! Some of those red stars are tiny. But we're talking about a real M9 here, and orbiting this thing wouldn't feel much warmer than orbiting Jupiter.
• I've included an appendix with lots of interesting and relevant stars, so you can invent your own hypotheses. I have a feeling that JMS is gonna stick with Epsilon Eridani, so we will just have to ignore the numbers he quotes for distance, and hope that Ted Turner colorizes the star in some future Special Edition.
Also via the 3D star maps page, a revelation: real star maps look exactly like the star maps in Escape Velocity.
Posted by Jon Rubin at 11:28 PM | Comments (0) | TrackBack
July 24, 2006
"The three most dangerous things in the world are a programmer with a soldering iron, a hardware type with a program patch, and a user with an idea."
In lieu of a real post tonight...
A geek moment.
So last Friday night, I left a party early so I could get home and watch Stargate—
—no, hold on, it gets geekier.—So I'm sitting at home alone on a Friday night—
—no, not yet—and I decide to Google myself—
—patience! even more geekiness ahead!—
—and I discover that I once submitted a link to Slashdot—wait, almost there—
—and I submitted this link to Slashdot in June of 1998.
And there we go. We have joy. Maximum geekitude attained.
Yes, when I was 15 years old, how did I spend my summer vacation? Apparently, submitting links to maps of the internet to Slashdot, that's how.
Plus, think about it: 1998. Slashdot hadn't even been around for a year yet, according to Wikipedia. This was before Jon Katz forever sullied the site. Over a half a year before the "Slashdot Effect" was coined...did they even have a user registration system or comment ratings back then?
Posted by Jon Rubin at 11:30 PM | Comments (1) | TrackBack
July 23, 2006
"Don't be small, Albert. Remember: you are a genius. So, so what if you masturbated this morning? This does not mean you are a bad scientist."
Some researchers at Cornell have devised a new light-scattering technique for rendering blond and brown hair in 3D computer graphics.
The problem is that light traveling through a mass of blond hair is not only reflected off the surfaces of the hairs, but passes through the hairs and emerges in a diffused form, from there to be reflected and transmitted some more.
The only method that can render this perfectly is "path-tracing," in which the computer works backward from each pixel of the image, calculating the path of each ray of light back to the original light source. Since this require hours of calculations, computer artists resort to approximations.
"People do something reasonable for one bounce and then assume it reflects diffusely," Marschner explained. In other words, he said, they assume that hair is opaque. "In light-colored hair it's important to keep track of the hair-to-hair scattering," he said.
Marschner and Moon's algorithm begins by tracing rays from the light source into the hair, using some approximations of the scattering and producing a map of where photons of light can be found throughout the volume of hair. Then it traces a ray from each pixel of the image to a point in the hair and looks at the map to decide how much light should be available there.
The result, in a test rendering of a swatch of blond hair, appears almost identical to a rendering by the laborious path-tracing method. Path tracing for the test required 60 hours of computation, while the new method took only 2.5 hours, the researchers report.
The Gusher: how high oil prices and the falling dollar interact
So, what we see above is that Americans continue to import more oil, at higher prices. Let's do a little basic micro economics here. If you raise prices and your customer buys more of your product, are you going to raise prices again?
Yeah, me too.
And this is part of why Bernanke's got a problem. Too much of all that money in the system is getting flushed into commodity speculation. It's dead easy money.
Bernanke needs to get people to stop buying so much oil. It's a weakness, a bull market that any idiot can exploit, and it's now becoming self-reinforcing as all bull markets (and bubbles) do at certain stages. The more money that is chasing a fixed number of barrels, the higher they get bid.
What is further clear from these charts is that Bernanke isn't tightening fast enough. He needs to stop pumping the gas pedal and slam on the brakes. The reason is that inflation is beginning to really hurt in the US, it's even getting to the point where so called core inflation (the inflation that measures, as Ritholz notes, what your life would be like if you didn't eat, have to pay a mortgage or property taxes, walked everywhere and didn't need to cool or heat your house) is beginning to show real inflation. Other measures of inflation have been overheated for some time now.
So the choice, as I noted before, remains the same. Slam on the braks and have a nasty recession - or ease the brakes on, have a nasty inflationary bout, and then have a nasty recession.
Scenario two will be chosen, because scenario one would lead to a Republican wipeout in November 2006.
Neuroscientists at Yale and Oxford have isolated the predecessor neurons that develop into the cerebral cortex in utero. Unfortunately, this interesting scientific observation will be exploited for political gain by the so-called "pro-life" crowd, no doubt. via
The findings published in Nature Neuroscience show that the first neurons, or "predecessors," as the researchers called them, are in place 31 days after fertilization. This is much earlier than previously thought and well before development of arms, legs or eyes.
Co-author Pasko Rakic, chair of the Department of Neurobiology and director of the Kavli Institute of Neuroscience at Yale, said the use of highly specific cell markers led the team to the surprising discovery of new types of neurons in the prospective cerebral cortex.
"We hypothesize that these predecessor neurons may be a transient population involved in determining the number of functional radial units including the human specific regions of the cerebral cortex mediating higher cognitive functions," Rakic said.
Until recently it was thought that cortical neurons were generated locally, but this research team describes a distinctive, widespread population of neurons situated beneath the surface of the human embryonic forebrain even before complete closure of the neural tube.
Predecessor cells, unlike mature nerve cells, do not have synaptic connection with other neurons. They do have long processes, or "tails," with one stretching out in front of the cell body and the other trailing behind. Analysis of the skeleton of these cells suggests that they migrate upwards in the surface of the developing brain and enter the future cortex.
As Billmon cogently explains, a regional conflict in the Middle East could easily lead to Iran cutting off the supply lines to coalition forces in Iraq, effectively losing an army. Mogadishu writ large. Academically, I've always felt that one of the dangers of invading Iraq was that it exposed and overextended the US military when it could be put to better uses, but it's only during this new crisis with Lebanon that the interrelatedness of all ME conflicts has really come to the fore for me. via
If the supply lines back to Kuwait were to be cut -- or even seriously interdicted -- the U.S. military presence in Iraq would quickly become untenable. I'm not even sure the Army could scrounge enough gas to keep the tanks and Humvees moving, given that Iraq already suffers from a severe refining capacity shortage and must import most of its gasoline from Kuwait.
In other words, in the event of a real world war -- as opposed to the kind that pundits pontificate about on Fox News -- Centcom would either have to "pacify" the transportation routes through southern Iraq quickly and ruthlessly (which might not be possible, given the troops available and the possibility some Iraqi units might turn on their putative allies) or try to evacuate some or most U.S. forces from Iraq, either by air or ground.
We're talking, on other words, about a potential debacle -- the worst U.S. military defeat since Pearl Harbor. Not because the Iranians are brilliant strategists or tough fighters (although they may be; we really don't know) but because the Iraq occupation has left the U.S. Army dangerously overextended, given its massive supply requirements.
Newly-released personal writings reveal what us Upright Citizens Brigade fans have known for years: Einstein was a horn-dog. Now, if only there's something in there about him traveling back in time to talk to Jesus, play cards with Jesus, shove Jesus! via
In 1919, Einstein divorced Mileva and married Elsa, but within four years he was in love with Bette Neumann, his secretary who was also the young niece of one of his friends. Many more liaisons followed.
The letters reveal that a beautiful Berlin socialite named Ethel Michanowski followed him to Oxford, only to discover that he was involved with a third woman.
According to excerpts of letters made available to reporters, Einstein discussed his extra-marital affairs openly with his family.
``It is true that M. followed me and her chasing after me is getting out of control," wrote Einstein to his stepdaughter in May 1931 of Michanowski's infatuation. ``I will tell her that she should vanish immediately. . . . Out of all the dames, I am in fact attached only to Mrs L. who is absolutely harmless and decent, and even with this there is no danger to the divine world order."
``I don't care what people are saying about me, but for mother and Mrs M. it is better that not every Tom, Dick and Harry gossip about it," he wrote.
``Mrs L." was Margarete Lenbach, another wealthy woman who used to send a chauffeur-driven car to collect Einstein for their late-night trysts.
But Einstein valued Michanowski's discretion, as he wrote to his second wife Elsa in 1931.
``Mrs. M. definitely acted according to the best Christian-Jewish ethics: 1) one should do what one enjoys and what won't harm anyone else; and 2) one should refrain from doing things one does not take delight in and which annoy another person. Because of 1) she came with me, and because of 2) she didn't tell you a word. Isn't that irreproachable?"
Posted by Jon Rubin at 10:25 PM | Comments (0) | TrackBack
July 22, 2006
~Cigarettes, they fill the gaps. / In our empty days. / In our broken teeth.~
The Agonist is up to Middle East Crisis Open Thread IV, and I fear Thread V will begin by the morrow. The Agonistas are doing a commendable job of collecting the latest headlines in those threads. Their coverage is as good if not better than it was during the invasion of Iraq. They're proving the efficacy of blogs for actually informing people about current events in a balanced way, rather than for spreading rhetoric.
ScatterChat facilitates secure and anonymous instant messaging over existing IM networks. via
It is a secure instant messaging client (based upon the Gaim software) that provides end-to-end encryption, integrated onion-routing with Tor, secure file transfers, and easy-to-read documentation.
Its security features include resiliency against partial compromise through perfect forward secrecy, immunity from replay attacks, and limited resistance to traffic analysis... all reinforced through a pro-actively secure design.
Engadget claims the next iPod will do ebooks—something that should have happened long ago, IMO.
We'd say the possibility is very real, since according to a source at a major publishing house, they were just ordered to archive all their manuscripts -- every single one -- and send them over to Apple's Cupertino HQ. A separate trusted source let us know that the next iPod will have a substantial amount of screen real estate (as we'd all suspected), as well as a book reading mode that pumps up the contrast and drops into monochrome for easy reading.
There's a Foo Fighters cover of the Jawbreaker song "Kiss the Bottle"...I just found out about it randomly googling for a quote to title this post with. And now, through a triumph of circular logic, the title is a quote from that song.
Sooo many other things I should post, but I'm feelin' lazy tonight.
Posted by Jon Rubin at 10:22 PM | Comments (0) | TrackBack
July 21, 2006
"Sea waves are green and wet, / But up from where they die / Rise others vaster yet, / And those are brown and dry."
For today, here's a bunch of stale links I've had tabbed out in my RSS aggregator far too long.
The universality of sand dunes, be they on Earth or Mars, is a result of self-organized criticality:
Where the dunes become sparser - for example, near that icy hill - they break apart into "barchans". These are crescent-shaped formations whose horns point downwind. Barchans are also found on the deserts of Earth, and surely on many other planets across the Universe. They are one of several basic dune patterns, an inevitable consequence of the laws of nature under fairly common conditions.
The upwind slope of a barchan is gentle, while the downwind slope is between 32 and 34 degrees. This is the "angle of repose" for sand - the maximum angle it can tolerate before it starts slipping down.
Barchans gradually migrate in the direction of the wind at speeds of about 1-20 meters per year, with small barchans moving faster than big ones. In fact, when they collide, the smaller barchans pass right through the big ones! So, they act like solitons in some ways.
What makes sand dunes interesting is that as they seem to enjoy living on the brink of danger. As the wind blows, they heap up until their slip face is right at the angle of repose... ready for landslides!
This is the idea of "self-organized criticality": some physical systems seem to spontaneously bring themselves towards critical points, without any need for us to tune their parameters to special values.
SOC occurs in sandpile models because one adds the sand extremely slowly, i.e., one grain at a time. Otherwise a critical state is not obtained. This makes SOC be a special example of dynamical critical phenomena in the case that the flux variable (here the rate of sand addition) is set to ε+, i.e., an infinitesimal value greater than zero. This formulation allows SOC to be studied using quantum field theory.
Malcolm Gladwell reviews a book about explanations:
In Tilly’s view, we rely on four general categories of reasons. The first is what he calls conventions—conventionally accepted explanations. Tilly would call “Don’t be a tattletale” a convention. The second is stories, and what distinguishes a story (“I was playing with my truck, and then Geoffrey came in . . .”) is a very specific account of cause and effect. Tilly cites the sociologist Francesca Polletta’s interviews with people who were active in the civil-rights sit-ins of the nineteen-sixties. Polletta repeatedly heard stories that stressed the spontaneity of the protests, leaving out the role of civil-rights organizations, teachers, and churches. That’s what stories do. As Tilly writes, they circumscribe time and space, limit the number of actors and actions, situate all causes “in the consciousness of the actors,” and elevate the personal over the institutional.
Then there are codes, which are high-level conventions, formulas that invoke sometimes recondite procedural rules and categories. If a loan officer turns you down for a mortgage, the reason he gives has to do with your inability to conform to a prescribed standard of creditworthiness. Finally, there are technical accounts: stories informed by specialized knowledge and authority. An academic history of civil-rights sit-ins wouldn’t leave out the role of institutions, and it probably wouldn’t focus on a few actors and actions; it would aim at giving patient and expert attention to every sort of nuance and detail.
Tilly argues that we make two common errors when it comes to understanding reasons. The first is to assume that some kinds of reasons are always better than others—that there is a hierarchy of reasons, with conventions (the least sophisticated) at the bottom and technical accounts at the top. That’s wrong, Tilly says: each type of reason has its own role.
Tilly’s second point flows from the first, and it’s that the reasons people give aren’t a function of their character—that is, there aren’t people who always favor technical accounts and people who always favor stories. Rather, reasons arise out of situations and roles. Imagine, he says, the following possible responses to one person’s knocking some books off the desk of another:
1. Sorry, buddy. I’m just plain awkward.
2. I’m sorry. I didn’t see your book.
3. Nuts! I did it again.
4. Why did you put that book there?
5. I told you to stack up your books neatly.
The lesson is not that the kind of person who uses reason No. 1 or No. 2 is polite and the kind of person who uses reason No. 4 or No. 5 is a jerk. The point is that any of us might use any of those five reasons depending on our relation to the person whose books we knocked over. Reason-giving, Tilly says, reflects, establishes, repairs, and negotiates relationships.
Douglas Hoftstadter, the fugue, and computer-generated music in the style of actual composers
Thinking in C is a huge Flash video tutorial.
Even my own hyperactive imagination is having a hard time wrapping itself around the idea. I'm familiar enough with Cold War history to know the United States has at least considered the first use of nuclear weapons before—in Korea and even in Vietnam—and I know it was long-standing U.S. strategic doctrine never to rule out a nuclear response to a Soviet conventional attack on Western Europe. But the current nuclear war gaming strikes me as much more likely to end in the real thing—partly because the neocons appear to have convinced themselves a "tactical" strike doesn't really count, partly because of what Hersh politely refers to as Bush's "messianic vision" (Cheney may have his finger on the bureaucracy, but Shrub is still the one with his finger on the button) but mostly because I think these guys really think they can get away with it. And they might be right.
I've been trying to picture what the world might look like the day after a U.S. nuclear strike on Iran, but I'm essentially drawing a blank. There simply isn't a precedent for the world's dominant superpower turning into a rogue state—much less a rogue state willing to wage nuclear war against potential, even hypothetical, security threats. At that point, we'd truly be through the looking glass.
One can assume (or at least hope) that first use of nuclear weapons would turn America into an international pariah, at least in the eyes of global public opinion. It would certainly mark the definitive end of the system of collective security—and the laws and institutions supporting that system—established in the wake of World War II. The UN Security Council would be rendered as pointless as the old League of Nations. The Nuremberg Principles would be as moot as the Geneva Conventions. (To the neocons, of course, these are all pluses.)
Nuclear first use would also shatter (or at least, radically transform) the political alliances that defined America's leadership role in the old postwar order. To the extent any of these relationships survived, they'd be placed on roughly the same basis as the current U.S. protectorate over Saudi Arabia—or, even worse, brought down to the level of the old Warsaw Pact. They would be coalitions of the weak, the vulnerable and the easily intimidated.
In other words, the current hegemony of American influence and ideas (backed by overwhelming military force) would be replaced by an overt dictatorship based—more or less explicitly—on fear of nuclear annihilation. U.S. foreign policy would become nothing more than a variation on the ancient Roman warning: For every one of our dead; 100 of yours. Never again would American rulers (or their foreign counterparts) be able to hide behind the comfortable fiction that the United States is just primus inter pares: first among equals. A country that nukes other countries merely on the suspicion that they may pose a future security threat isn't the equal of anybody. America would stand completely alone: hated by many, feared by all, admired only by the world's other tyrants.
Mutiny at the Supreme Court (the Hamdan and Padilla decisions)
The Logic Alphabet turns Booleans into a physical toy that can be rotated into valid declarations.
Glenn Greenwald explains that we are not at war, something conservatives always seem to forget...except when it provides legal cover.
Who might be able to explain to Law Professor Reynolds why it is plainly false to assert, as he did, that Congress has declared war -- either against Al Qaeda or Iraq? Let's see . . . who would volunteer for this job . . . how about Attorney General Alberto Gonzales, testifying before the Senate Judiciary Committee.
Or how about the Justice Department's 42-page memorandum from January 19, 2006, defending the President's right to eavesdrop on Americans in violation of the law.
There are all kinds of issues surrounding the Bush administration's terrorism arguments which are subject to debate. Whether we are a country "at war" is not one of them, as Bush's own Attorney General, and as his administration's Justice Department, have made quite clear.
Even they have expressly acknowledged that there is no declaration of war from Congress with regard to either Iraq or al Qaeda, and to state otherwise -- as Instapundit did twice, including once after it was pointed out to him that there has been no declaration of war -- requires either great confusion or outright ignorance with regard to Article I, Section 8 of the Constitution specifically, and to declarations of war generally.
The notion that we are in "a time of war" is used to "justify" a whole array of extremist and even illegal policies, and much attention is often paid to the fact that such conduct, as the Founders stressed, does not become any more acceptable because we are at war.
“This guy gets pulled over on suspicion of a DUI,” she said, “And it turns out that he only speaks Spanish. So the cop radios for a Spanish-speaking colleague. A second officer shows up, reads the driver his rights in Spanish off of a little card that all cops carry, and they administer the breathalyzer test. Sure enough, the guy is soused.
“We figure this case is a slam dunk. But a few weeks later the driver’s lawyer submits a motion to have the results of the breathalyzer voided, saying that the defendant didn’t understand his rights before we gave him the test. And we’re all, like, ‘Nuh-uh! We read him his rights. In Spanish, even.’
“But the defense somehow got a copy of the Spanish language card that the officer read from, and noticed that the little squiggle was missing from above an ‘n’ in the sentence: ‘¿Tiene veinteuno años?’ In English that literally translates to ‘Do you have 21 years?’—in other words, this was just a routine question to make sure the guy was an adult. But without the tilde over the ‘n’, the word ‘años’ becomes ‘anos’—Spanish for ‘anuses.’
“They’re claiming that the driver thought the officer asked ‘Do you have 21 anuses’, despite the fact that the officer reading the card spoke fluent Spanish and would have pronounced it ‘años’ anyway. And the defendant said ‘si.’ We’re supposed to believe that the guy genuinely thought he was being asked if he had multiple anuses and answered with an enthusiastic ‘yes!’
“The best part is that the defense attorney can’t even bring himself to say the word ‘anus.’ Instead, he calls it ‘the back region.’ We’re going in front of a judge next week, and I’m going to make a point of saying the word ‘anus’ as many times as I can during the proceeding. I even got them to call the legal brief ‘The Anus Motion,’ so he won’t even be able to refer to it by title.
Stoner hacker Gary McKinnon claims NASA is involved in UFOs. "Claims" being the key word.
GM: I got one picture out of the folder, and bearing in mind this is a 56k dial-up, so a very slow internet connection, in dial-up days, using the remote control programme I turned the colour down to 4bit colour and the screen resolution really, really low, and even then the picture was still juddering as it came onto the screen.
But what came on to the screen was amazing. It was a culmination of all my efforts. It was a picture of something that definitely wasn't man-made.
It was above the Earth's hemisphere. It kind of looked like a satellite. It was cigar-shaped and had geodesic domes above, below, to the left, the right and both ends of it, and although it was a low-resolution picture it was very close up.
This thing was hanging in space, the earth's hemisphere visible below it, and no rivets, no seams, none of the stuff associated with normal man-made manufacturing.
SK: Is it possible this is an artist's impression?
GM: I don't know... For me, it was more than a coincidence. This woman has said: "This is what happens, in this building, in this space centre". I went into that building, that space centre, and saw exactly that.
SK: Do you have a copy of this? It came down to your machine.
GM: No, the graphical remote viewer works frame by frame. It's a Java application, so there's nothing to save on your hard drive, or at least if it is, only one frame at a time.
SK: So did you get the one frame?
GM: No.
SK: What happened?
GM: Once I was cut off, my picture just disappeared.
SK: You were actually cut off the time you were downloading the picture?
GM: Yes, I saw the guy's hand move across.
The new CIA director refuses to deny he spied on Bush's political opposition when he lead the NSA's illegal domestic operations.
When Hayden dodged the question, the questioner repeated, "No, I asked, are you targeting us and people who politically oppose the Bush government, the Bush administration? Not a fishing net, but are you targeting specifically political opponents of the Bush administration?" Hayden looked at the questioner, and after a silence called on a different questioner. (Hayden National Press Club remarks, 1/23/06)
This past spring, a bunch of NeXT execs left Apple...not sure what that means.
Nancy Heinen, Apple's General Counsel and Secretary, quietly left the company for unknown reasons, AppleInsider reported. Heinen is the third senior executive to leave Apple is the last six weeks.
Ms. Heinen joins Avie Tevanian, former Chief Software Technology Officer, and John Rubinstein, former Senior Vice President of the iPod division, in departing from the company. All three joined Apple in 1997 following the acquisition of Steve Jobs' NeXT Software; their concurrent might signal a "changing of the guard" at the company.
Thanks to legal hero Eliot Spitzer, Universal Music's been busted for payola, along with most of the other big labels.
Most notably UMG and its labels--Def Jam, Interscope, Universal Motown Recordings Group, Uni-South, Universal Nashville and Verve--have agreed to stop making payments and providing expensive gifts to radio stations and their employees in return for airplay of particular artists’ songs. UMG used such tactics to secure airplay for Nick Lachey, Ashlee Simpson, Brian McKnight, Big Tymers, Lindsay Lohan and others.
Among the egregious violations cited in the Spitzer probe: Universal Motown spent close to $300,000 in July 2003 to drive airplay of Lumidee’s “Dream”; and the program director at WBEE (Rochester, NY) asked Uni-South to pay for a $2,500 laptop computer for the station in exchange for the station adding two songs, one by Joe Nichols and the other by McHayes.
...still got dozens and dozens of tabs open in NetNewsWire....oh well.
Posted by Jon Rubin at 01:29 PM | Comments (0) | TrackBack
July 20, 2006
"The world of men is dreaming, it has gone mad in its sleep, and a snake is strangling it, but it can’t wake up."
The feds and AT&T were just denied their motion to dismiss the domestic NSA internet spying lawsuit. That's the NSA scandal wherein AT&T forwards all the data from their peering sites (where they exchange data with other major internet backbones) to the NSA, infringing on the privacy of pretty much every American without any legal basis, even under the USA PATRIOT Act. This is the program that uses advanced network-sniffers from an NSA-spawned commercial entity called Narus to watch over the shoulder of millions of Americans at a time as they surf the web, chat with friends, and use e-mail.
In a 72-page written decision (.pdf) issued Thursday, U.S. District Court chief judge Vaughn Walker rejected the government's argument that merely allowing the case to proceed would cause critical harm to U.S. national security -- a ruling that marks a significant victory for EFF, and puts a rare limitation on the reach of the president's "state secrets privilege" to sweep alleged illegal government activities under the cloak of national security.
This, by the way, has nothing to do with the "War on Terror." Bush authorized the NSA to spy on Americans' internet traffic within days of stealing the Oval Office.
81. Within eleven (11) days of the onset of the Bush administration, and at least seven (7) months prior to the attacks of September 11, 2001, defendant ATT began development of a center for monitoring long distance calls and internet transmissions and other digital information for the exclusive use of the NSA.
82. The center was put into development by ATT following a proposal by the NSA for the construction and development of a network operations center identical to ATT's own network operations center located in Bedminster, New Jersey for the exclusive use of the NSA.
83. The NSA proposal was accepted by the ATT sales division and referred to ATT Solutions, an ATT project development division situated in Florham Park, New Jersey.
84. The NSA proposal sought construction of a duplicate ATT Network Operations Center for the exclusive use of the NSA with the capacity to monitor all calls and internet traffic placed on the ATT long distance network, as well as ATT's wide area, fiber optic, T-1, T-3, T-5 and high speed data networks.
85. Such a data center would also enable the NSA to tap into any call placed on the ATT network and to monitor the contents of all digital information transmitted over the ATT network.
86. The project was described in the ATT sales division documents as calling for the construction of a facility to store and retain data gathered by the NSA from its domestic and foreign intelligence operations but was to be in actuality a duplicate ATT Network Operations Center for the use and possession of the NSA that would give the NSA direct, unlimited, unrestricted and unfettered access to all call information and internet and digital traffic on ATT's long distance networks.
87. Said data center would enable the NSA to tap into any phone line and to monitor any digital transfer of information on ATT's networks including voice telephone calls, facsimile transmission and all internet traffic.
88. Such project was in development not later than February 1, 2001, within eleven (11) days of the onset of the Bush Administration.
89. The NSA program was initially conceived at least one year prior to 2001 but had been called off; it was reinstated within 11 days of the entry into office of defendant George W. Bush.
90. The NSA program was code-named Pioneer-Groundbreaker and was also known at ATT Solutions division as GEMS (Groundbreaker Enterprise System).
91. International Business Machines Corporation (IBM) was one of the parties working with ATT and the NSA to develop the monitoring center and IBM personnel participated in meetings with ATT and NSA officials in the development of the monitoring center.
92. Among the purposes of the Pioneer-Groundbreaker project was the storing and monitoring of all phone call information coming across ATT's networks; by means of this program NSA sought to duplicate all of the phone call information that came across ATT's networks for real time, contemporaneous analysis or, alternately, for downloading and later use by the NSA.
93. The proposed project was to be a storage entity modeled on ATT's network operations center in Bedminster, New Jersey, and would have the capability to monitor all data and traffic that came across ATT lines, including ATT traffic and traffic originating from other carriers that used ATT lines or that sent calls to ATT customers.
94. The NSA was seeking to duplicate the ATT network operations center and sought by means of the Pioneer-Groundbreaker program the ability to monitor all traffic coming across ATT's network.
Isbell suggests instead that primates developed good close-up eyesight to avoid a dangerous predator -- the snake.
"A snake is the only predator you really need to see close up. If it's a long way away it's not dangerous," Isbell said.
Neurological studies by others show that the structure of the brain's visual system does not actually fit with the idea that vision evolved along with reaching and grasping, Isbell said. But the visual system does seem to be well connected to the "fear module," brain structures involved in vigilance, fear and learning.
Fossils and DNA evidence show that snakes were likely the first serious predators of modern mammals, which evolved about 100 million years ago. Fossils of snakes with mouths big enough to eat those mammals appear at about the same time. Other animals that could have eaten our ancestors, such as big cats, and hawks and eagles, evolved much later.
In August of 2004, NASA had trouble when the Spirit rover on Mars insisted it was the year 2038. Did aliens send the robot hurtling through time, or was it a foreshadowing of Unix's Y2K.038 problem?
King Tut had glass before there was glass. via
In 1996 in the Egyptian Museum in Cairo, Italian mineralogist Vincenzo de Michele spotted an unusual yellow-green gem in the middle of one of Tutankhamun's necklaces.
The jewel was tested and found to be glass, but intriguingly it is older than the earliest Egyptian civilisation.
Working with Egyptian geologist Aly Barakat, they traced its origins to unexplained chunks of glass found scattered in the sand in a remote region of the Sahara Desert.
The simulation revealed that an impactor could indeed generate a blistering atmospheric fireball, creating surface temperatures of 1,800C, and leaving behind a field of glass.
"What I want to emphasise is that it is hugely bigger in energy than the atomic tests," says Boslough. "Ten thousand times more powerful."
Posted by Jon Rubin at 09:22 PM | Comments (0) | TrackBack
July 19, 2006
"Vulgarity is not a sin against God, but against polite society."
Double-Barrel Cigarette Holder
I am happy, because Carnivale Season 2 is out on DVD finally. I was beginning to think HBO's betrayal of the series had no bounds.
Posted by Jon Rubin at 09:45 PM | Comments (0) | TrackBack
July 18, 2006
"My real problem is that they let the trickster Gods into it. Like farting. You KNOW farting was Pan's idea. It's just exactly his style."
Nerd wrath, or, how to build a bazooka out of Estes model rockets and some plastic piping. Complete with pretty long-exposure photography.
how scary is it that there are people on this site that could probably design weapons better than entire terrorist organizations
Microsoft's got a new "iPod-slayer" called Zune, but of course Redmond is screwing the whole thing up by thinking more features makes up for less storage. Not a smart idea when video is supposed to be a key feature...plus, Microsoft's forgetting that Apple has its annual iPod refresher coming up soon. Major new changes are unlikely until January, but price drops could come as soon as August. Then, Zune's 30 gigs will look even more paltry. via
According to the sources, the device will offer 30GB of storage, though it will deliver the "same pricing, look and feel as the 60GB iPod". That would suggest a retail price of $399, the price point for the high-end iPod. Immediately, the sticker is likely to draw comparisons to the comparable 30GB iPod, which is available for $299.
Tim Boucher writes about Jesus, the Trickster:
I realize that a lot of traditionalists will gasp and back away from the idea that Jesus was trying to “trick” anybody. How could anybody who proclaimed that they are “the way, the Truth and the life” be considered to be a trickster? In order to dismantle that notion and re-assemble it into something more useful, we have to decide what the nature of “Truth” is. Is the truth something simple and easy? It can be, but it can also be something earth-shattering, complex and difficult. It can be something that we can’t for the life of us ever possibly put into words. In that sense, Jesus could spread the ineffable Truth simply by confounding and confusing and getting us out of our old habits and patterns of thinking.
More specifically though and more in keeping with the Trickster myths, Jesus actually did pull some crazy stunts. Didn’t he? What about that whole thing where he died and then came back to life again?
“Ha! Gotcha, sucker!” we can imagine him saying to the Devil as pulls a sort of Three Stooges routine, pokes the devil in the eye smacks him on the head and floats up out of Hell, throwing down the power of Death once and for all. Ttricksters, too, are often identified with culture heroes who bring boons to the people, such as Prometheus who brought us fire. Jesus certainly fits the bill here as well. Jesus tricked the Jews and the Romans with this stunt too. He proved that the power of his Kingdom transcended the pitiful laws of this material world we inhabit. His teachings also invert power structures and invite creative solutions to old problems and assumptions which we thought there was no way out of. In fact, most of his teachings, life and even his miracles can be seen with a new beauty, humor and irony when viewed through the lens of the Trickster.
And via that last link, the Yoruba story of Eshu:
Eshu was walking down the road one day, wearing a hat that was red on one side and blue on the other. Sometime after he departed, the villagers who had seen him began arguing about whether the stranger's hat was blue or red. The villagers on one side of the road had only been capable of seeing the blue side, and the villagers on the other side had only been capable of seeing the red half. They nearly fought over the argument, until Eshu came back and cleared the mystery, teaching the villagers about how one's perspective can alter a person's perception of reality, and that one can be easily fooled. In other versions of this tale, the two tribes were not stopped short of violence; they actually annihilated each other, and Eshu laughed at the result, saying "Bringing strife is my greatest joy".
Posted by Jon Rubin at 10:45 PM | Comments (1) | TrackBack
July 17, 2006
"And as all things have been & arose from one by ye mediation of one: so all things have their birth from this one thing by adaptation."
The second Middle East Crisis Open Thread over at the Agonist is probably the best place to go for headlines relevant to that particular clusterfuck.
All beings replicate their DNA the same way, be they prokaryotic or eukaryotic, even including the archaeans.
In two papers that will be concurrently published in the August edition of the journal Nature Structural and Molecular Biology (now available on-line), the researchers report the identification of a helical substructure within a superfamily of proteins, called AAA+, as the molecular “initiator” of DNA replication in a bacteria, Escherichia coli (E. coli), and in a eukaryote, Drosophila melanogaster, the fruit fly. Taken with earlier research that identified AAA+ proteins at the heart of the DNA replication initiator in archaea organisms, these new findings indicate that DNA replication is an ancient event that evolved millions of years ago, prior to when Archae, Bacteria and Eukarya split into separate domains of life.
For the E.coli study, Berger and his team utilized the exceptionally bright and intense x-rays of Beamline 8.3.1 at Berkeley Lab’s Advanced Light Source synchrotron. With the data gathered at this protein crystallography facility, Berger and his team assembled a high-resolution model of the molecular structure of a protein known as DnaA, which is a member of the AAA+ family. While it has long been known that DnaA controls the process of initiating DNA replication in bacteria, the molecular details of its myriad activities have until now been a mystery.
Berger’s team found that when the DnaA protein binds with adenosine triphosphate or ATP, the nucleotide molecule that supplies energy to all components of a cell, the ring-shaped AAA+ proteins assemble into a right-handed spiraling superstructure. This arrangement was unexpected, because in other functional AAA+ complexes, the ring assemblies are closed. In addition, the architecture indicated that the AAA+ superhelix will wrap coils of the DNA double-helix around its exterior, causing the familiar “spiral staircase” of the DNA to deform as a first step in the separation and unwinding of its two gene-carrying strands.
Studies over the past decade have demonstrated that all of the multiple events that initiate DNA replication in a eukaryote are directed by a single complex of proteins called the origin recognition complex (ORC). However, until now, models of the ORC proteins have lacked sufficient detail to identify the structure of the initiator. In their Drosophila study, Nogales and Botchan and their collaborators studied fruit fly ORC using single-particle electron microscopy. Their images revealed for the first time how the ORC when bound to ATP forms a AAA+ helical structure much like the DnaA superhelix found by Berger and his team in their E.coli study.
The idea that all three domains of life share the same DNA replication initiator is new and will require some re-thinking on the part of biologists who study eukaryotes. Re-thinking will also be required for models of DNA replication that predicted initiators would have similar structures to the protein “clamps” and “clamp loaders” already identified as key mechanisms in the DNA replication process.
Said Berger, “Our work shows that there are major structural distinctions between assembled initiator and clamp loader complexes. This not only has important implications for the respective functions of these different mechanisms, it also calls into question some cherished models in the field.”
The two studies by Nogales, Berger, Botchan and their colleagues also show how when nature finds a mechanism that works well, such a mechanism is conserved through evolution.
cat and MPEG-2: there's a first time everything, even for learning something from a LiveJournal comment
Another thing you should know is that VIDEO_TS files, being mpeg2 files, can be stapled together with cat (!) and they'll still play. Like:
cat a.vob b.vob c.vob > finalmovie.mpeg2
Posted by Jon Rubin at 10:49 PM | Comments (0) | TrackBack
July 16, 2006
~So I'm writing everything down in a spiral notebook~
Finally, an explanation for MySpace's popularity:
myspace is popular because kids remember what the internet looked like in 1996 and are nostalgic for it.
posted by StrasbourgSecaucus at 3:09 PM EST on July 16 [+fave] [!]
Spiral notebooks were new once: via
Coil springs form flexible bindings for a new type of memorandum books.
Weird street art installations of mannequins in impossible situations
Posted by Jon Rubin at 08:35 PM | Comments (0) | TrackBack
July 15, 2006
"We cannot learn the cipher / That's writ upon our cell, / Stars help us by a mystery / Which we could never spell."
Spinons and holons have been observed for the first time. This is big for the sort of technology in Hacking Matter, I think.
Just as the body and wheels of a car are thought to be intrinsic parts of a whole, incapable of separate and independent actions, i.e., the body goes right while the wheels go left, so, too, are electrical charge and spin intrinsic components of an electron. Except, according to theory, in one-dimensional solids, where the collective excitation of a system of electrons can lead to the emergence of two new particles called “spinons” and “holons.” A spinon carries information about an electron’s spin and a holon carries information about its charge, and they do so as separate and independent entities. Numerous experiments have tried to confirm the creation of spinons and holons, referred to as spin-charge separation, but it took the technological advantages offered at ALS Beamline 7.0.1, also known as the Electronic Structure Factory (ESF), to achieve success.
In a paper published in the June 2006 issue of the journal Nature-Physics, researchers have reported the observation of distinct spinon and holon spectral signals in one-dimensional samples of copper oxide, SrCuO2, using the technique known as ARPES, for angle-resolved photoemission spectroscopy.
The idea behind spin-charge separation is that electrons behave differently when their range of motion is restricted to a single dimension, as opposed to three or even two dimensions. When moving through one dimension, for example, the electrons are lined up head-to-tail, making the repulsive force between their negative electrical charges overridingly dominant. The restricted movement of electrons through one-dimensional material was expected to give rise to collective effects that would be strong enough to break the information flow of spin and charge from a single electron.
ARPES is an excellent tool for observing spin-charge separation and other collective effects involving electrons. In this technique, x-rays are flashed on a sample causing electrons to be emitted through the photoelectric effect. Measuring the kinetic energy of emitted electrons and the angles at which they are ejected identifies their velocity and scattering rates. This in turn yields a detailed picture of the electron energy spectrum. Ordinarily, the removal of an electron from a crystal creates a hole, a vacant positively-charged energy space. This hole carries information on both the spin and the charge, as observed in a single peak of an ARPES spectrum. If spin-charge separation occurs, the hole decays into a spinon and a holon and two peaks in the ARPES spectrum are observed.
ALS Beamline 7.0.1 utilizes a state-of-the-art undulator magnetic insertion device to generate beams of x-rays with properties similar to that of a laser. These coherent and tunable x-ray beams are a hundred million times brighter than those from the best x-ray tubes and provide an exceptionally high degree of angular resolution for ARPES experiments.
Another area in which spinons and holons could play an important role is in the development of nanowires, one-dimensional hollow tubes through which the movement of electrons is so constrained that quantum effects dominate.
Nanowires are expected to be key components in future nanotechnologies, including optoelectronics, biochemical sensing, and thermoelectrics.
The creation of spinons and holons in one-dimensional systems is also expected to have an impact on the future of spintronics, a technology in which the storage and movement of data will be based on the spin of electrons, rather than just on charge, as with our current electronic technology.
Thanks to Uncle Sam, there are a bunch of pretty pretty rare old star charts available online at really high resolutions that are great for desktop backgrounds. via
I should really have reversed those two links, so the ultra-nifty sky maps didn't get lost in all the gibberish about electrons and spinons and holons and, as Monty Burns would say, "other nuclear bric-a-brac." Oh well.
Of course, when I say "gibberish," I mean it lovingly, following the dubious etymology laid forth by Samuel Johnson in his "Plan of an English Dictionary":
The present usage of spelling, where the present usage can be distinguished, will, therefore, in this work, be generally followed; yet there will be often occasion to observe, that it is in itself inaccurate, and tolerated rather than chosen; particularly when, by the change of one letter or more, the meaning of a word is obscured, as in farrier for ferrier, as it was formerly written, from ferrum, or fer; in gibberish for gebrish, the jargon of Geber, and his chymical followers, understood by none but their own tribe.
Geber was none other than Jabir ibn Hayyan, the father of (al)chemistry.
Jabir is mostly known for his contributions to chemistry. He emphasised systematic experimentation, and did much to free alchemy from superstition and turn it into a science. He is credited with the invention of many types of now-basic chemical laboratory equipment, and with the discovery and description of many now-commonplace chemical substances and processes – such as the hydrochloric and nitric acids, distillation, and crystallisation – that have become the foundation of today's chemistry and chemical engineering.
His books strongly influenced the medieval European alchemists and justified their search for the philosopher's stone.
In spite of his leanings toward mysticism (he was considered a Sufi) and superstition, he more clearly recognised and proclaimed the importance of experimentation. "The first essential in chemistry", he declared, "is that you should perform practical work and conduct experiments, for he who performs not practical work nor makes experiments will never attain the least degree of mastery."
Jabir is also credited with the invention and development of several chemical instruments that are still used today, such as the alembic, which made distillation easy, safe, and efficient. By distilling various salts together with sulfuric acid, Jabir discovered hydrochloric acid (from salt) and nitric acid (from saltpeter). By combining the two, he invented aqua regia, one of the few substances that can dissolve gold. Besides its obvious applications to gold extraction and purification, this discovery would fuel the dreams and despair of alchemists for the next thousand years. He is also credited with the discovery of citric acid (the sour component of lemons and other unripe fruits), acetic acid (from vinegar), and tartaric acid (from wine-making residues).
Jabir applied his chemical knowledge to the improvement of many manufacturing processes, such as making steel and other metals, preventing rust, engraving gold, dyeing and waterproofing cloth, tanning leather, and the chemical analysis of pigments and other substances. He developed the use of manganese dioxide in glassmaking, to counteract the green tinge produced by iron — a process that is still used today. He noted that boiling wine released a flammable vapor, thus paving the way to Al-Razi's discovery of ethanol.
The seeds of the modern classification of elements into metals and non-metals could be seen in his chemical nomenclature. He proposed three categories: "spirits" which vaporise on heating, like camphor, arsenic, and ammonium chloride; "metals", like gold, silver, lead, copper, and iron; and "stones" that can be converted into powders.
Several technical terms introduced by Jabir, such as alkali, have found their way into various European languages and have become part of scientific vocabulary.
Jabir's alchemical investigations revolved around the ultimate goal of takwin — the artificial creation of life. Alchemy had a long relationship with Shi'ite mysticism; according to the first Imam, Ali ibn Abi Talib, "alchemy is the sister of prophecy". Jabir's interest in alchemy was probably inspired by his teacher Ja'far al-Sadiq, and he was himself called "the Sufi", indicating that he followed the ascetic form of mysticism within Islam.
In his writings, Jabir pays tribute to Egyptian and Greek alchemists Hermes Trismegistus, Agathodaimon, Pythagoras, and Socrates. He emphasises the long history of alchemy, "whose origin is Arius ... the first man who applied the first experiment on the [philosopher's] stone... and he declares that man possesses the ability to imitate the workings of Nature" (Nasr, Seyyed Hossein, Science and Civilization of Islam).
Jabir states in his Book of Stones (4:12) that "The purpose is to baffle and lead into error everyone except those whom God loves and provides for". His works seem to have been deliberately written in highly esoteric code, so that only those who had been initiated into his alchemical school could understand them. It is therefore difficult at best for the modern reader to discern which aspects of Jabir's work are to be read as symbols (and what those symbols mean), and what is to be taken literally. Because his works rarely made overt sense, the term gibberish is believed to have originally referred to his writings (Hauck, p. 19).
Jabir's alchemical investigations were theoretically grounded in an elaborate numerology related to Pythagorean and Neoplatonic systems. The nature and properties of elements was defined through numeric values assigned the Arabic consonants present in their name, ultimately culminating in the number 17.
To Aristotelian physics, Jabir added the four properties of hotness, coldness, dryness, and moistness (Burkhardt, p. 29). Each Aristotelian element was characterised by these qualities: Fire was both hot and dry, earth cold and dry, water cold and moist, and air hot and moist. This came from the elementary qualities which are theoretical in nature plus substance. In metals two of these qualities were interior and two were exterior. For example, lead was cold and dry and gold was hot and moist. Thus, Jabir theorised, by rearranging the qualities of one metal, based on their sulfur/mercury content, a different metal would result. (Burckhardt, p. 29) This theory appears to have originated the search for al-iksir, the elusive elixir that would make this transformation possible — which in European alchemy became known as the philosopher's stone.
Jabir also made important contributions to medicine, astronomy, and other sciences. Only a few of his books have been edited and published, and fewer still are available in translation. The Geber crater, located on the Moon, is named after him.
Posted by Jon Rubin at 11:01 PM | Comments (0) | TrackBack
July 14, 2006
~You know I like to die for awhile / Everyday in the afternoon~
If you want to know what's going on in the Middle East, the only advice (and limited it is) I can give you is to read The Agonist. Their Middle East Crisis Open Thread is particularly informative. And, of course, terribly depressing.
Metcalfe's Law is wrong. It said that the value of a network, x, as it increases in network members, n, is described by the equation x=n^2. Anotherwords, it said the value of a network was proportional to the square of the network's users. Instead, that link declares it should be x=n•log(n). My suspicion—and this has no basis in anything and I haven't even graphed it and my total knowledge of information theory is that it was started by a guy named Claude—is that Euler has to be involved somewhere and maybe x=n•ln(n) would be more correct. via
Ah, isn't the Billy Goats Gruff a great fairy tale? I know I think so. I guess a guy on acid in Colorado thought the same thing: 'Bridge Troll' Arrested After Confrontation With Deputy. He was charging people a buck to cross a bridge in a park, claiming it was his and he was the troll who lived under it. Do click—the mug shots of him and his buddy are priceless. via
Police said that Hibbs insisted he was a troll and owned the bridge the deputy was trying to cross.
Witnesses told police that Hibbs and Bradley Boville, 19, were demanding $1 from joggers and bikers who attempted to cross the bridge.
The off-duty deputy, who was not identified, told police the confrontation with Hibbs started after the man hit his bike with a broken golf club when he forced his way past without paying.
Boville, who was with Hibbs, reportedly told police that they had consumed LSD and that Hibbs was having a bad trip.
Police said they confiscated a large marijuana joint rolled in $1 bills at the scene and then searched Boville's apartment and recovered drugs and drug paraphernalia.
Posted by Jon Rubin at 11:01 PM | Comments (0) | TrackBack
July 13, 2006
"Stranger things have happened!" "Only two spring to mind, Lister: the spontaneous combustion of the Mayor of Warsaw in 1546 and that incident in 12th century Burgundy when it rained herring."
There's some nice video footage of Final Fantasy III for the DS on YouTube. I cannot wait for this game. via
Robert Anton Wilson has been deathly ill of late. =( via
Researchers have discovered how spiders fly by threading the winds.
By casting a thread of silk into the breeze spiders are able to ride wind currents away from danger or to parachute into new areas. Often they travel a few metres but some spiders have been discovered hundreds of miles out to sea.
The new Rothamsted mathematical model allows for elasticity and flexibility of a ballooning spider's dragline – and when a dragline is caught in turbulent air the model shows how it can become highly contorted, preventing the spider from controlling the distance it travels and propelling it over potentially epic distances.
Posted by Jon Rubin at 10:44 PM | Comments (0) | TrackBack
July 12, 2006
"Realize these things are being done by primates—by apes dressed up in funny 'customes' [sic], like chimps who drive motorcycles in circuses—[...] it's quite astounding that the apes can handle the machinery and walk upright and so on."
md5 reverse lookup is like the Rainbow Table but for MD5—that is, it's a big hash table.
MD5 sums (see RFC 1321 - The MD5 Message-Digest Algorithm) are used as a one-way hash of data. Due to the nature of the formula used, it is impossible to reverse it. To find out what the source data was, one would traditionally attempt every single possible input value until they found the solution.
Even on fast machines this is difficult. To find the input value for a single MD5 will take some two weeks.
Using the disk space / speed trade-off, this database was started.
A helpful professor has provided definitive mathematical proof of the inefficacy of the NSA's domestic spying programs. via
What is the probability that people are terrorists given that NSA's mass surveillance identifies them as terrorists? If the probability is zero (p=0.00), then they certainly are not terrorists, and NSA was wasting resources and damaging the lives of innocent citizens. If the probability is one (p=1.00), then they definitely are terrorists, and NSA has saved the day. If the probability is fifty-fifty (p=0.50), that is the same as guessing the flip of a coin. The conditional probability that people are terrorists given that the NSA surveillance system says they are, that had better be very near to one (p=1.00) and very far from zero (p=0.00).
The mathematics of conditional probability were figured out by the Scottish logician Thomas Bayes. If you Google "Bayes' Theorem", you will get more than a million hits. Bayes' Theorem is taught in all elementary statistics classes. Everyone at NSA certainly knows Bayes' Theorem.
To know if mass surveillance will work, Bayes' theorem requires three estimations:
1. The base-rate for terrorists, i.e. what proportion of the population are terrorists;
2. The accuracy rate, i.e., the probability that real terrorists will be identified by NSA;
3. The misidentification rate, i.e., the probability that innocent citizens will be misidentified by NSA as terrorists.
No matter how sophisticated and super-duper are NSA's methods for identifying terrorists, no matter how big and fast are NSA's computers, NSA's accuracy rate will never be 100% and their misidentification rate will never be 0%. That fact, plus the extremely low base-rate for terrorists, means it is logically impossible for mass surveillance to be an effective way to find terrorists.
The US Census shows that there are about 300 million people living in the USA.
Suppose that there are 1,000 terrorists there as well, which is probably a high estimate. The base-rate would be 1 terrorist per 300,000 people. In percentages, that is .00033%, which is way less than 1%. Suppose that NSA surveillance has an accuracy rate of .40, which means that 40% of real terrorists in the USA will be identified by NSA's monitoring of everyone's email and phone calls. This is probably a high estimate, considering that terrorists are doing their best to avoid detection. There is no evidence thus far that NSA has been so successful at finding terrorists. And suppose NSA's misidentification rate is .0001, which means that .01% of innocent people will be misidentified as terrorists, at least until they are investigated, detained and interrogated. Note that .01% of the US population is 30,000 people. With these suppositions, then the probability that people are terrorists given that NSA's system of surveillance identifies them as terrorists is only p=0.0132, which is near zero, very far from one. Ergo, NSA's surveillance system is useless for finding terrorists.
Suppose that NSA's system is more accurate than .40, let's say, .70, which means that 70% of terrorists in the USA will be found by mass monitoring of phone calls and email messages. Then, by Bayes' Theorem, the probability that a person is a terrorist if targeted by NSA is still only p=0.0228, which is near zero, far from one, and useless.
Suppose that NSA's system is really, really, really good, really, really good, with an accuracy rate of .90, and a misidentification rate of .00001, which means that only 3,000 innocent people are misidentified as terrorists. With these suppositions, then the probability that people are terrorists given that NSA's system of surveillance identifies them as terrorists is only p=0.2308, which is far from one and well below flipping a coin. NSA's domestic monitoring of everyone's email and phone calls is useless for finding terrorists.
NSA knows this. Bayes' Theorem is elementary common knowledge. So, why does NSA spy on Americans knowing it's not possible to find terrorists that way? Mass surveillance of the entire population is logically sensible only if there is a higher base-rate.
Instead of presuming there are 1,000 terrorists in the USA, presume there are 1 million terrorists. Americans have gone paranoid before, for example, during the McCarthyism era of the 1950s. Imagining a million terrorists in America puts the base-rate at .00333, and now the probability that a person is a terrorist given that NSA's system identifies them is p=.99, which is near certainty. But only if you are paranoid. If NSA's surveillance requires a presumption of a million terrorists, and if in fact there are only 100 or only 10, then a lot of innocent people are going to be misidentified and confidently mislabeled as terrorists.
Also, mass surveillance of the entire population is logically plausible if NSA's domestic spying is not looking for terrorists, but looking for something else, something that is not so rare as terrorists. For example, the May 19 Fox News opinion poll of 900 registered voters found that 30% dislike the Bush administration so much they want him impeached. If NSA were monitoring email and phone calls to identify pro-impeachment people, and if the accuracy rate were .90 and the error rate were .01, then the probability that people are pro-impeachment given that NSA surveillance system identified them as such, would be p=.98, which is coming close to certainty (p=1.00). Mass surveillance by NSA of all Americans' phone calls and emails would be very effective for domestic political intelligence.
Monkeys are statistically indistinguishable from most stock-market investors. via
The capuchin is a New World monkey, brown and cute, the size of a scrawny year-old human baby plus a long tail. ''The capuchin has a small brain, and it's pretty much focused on food and sex,'' says Keith Chen, a Yale economist who, along with Laurie Santos, a psychologist, is exploiting these natural desires -- well, the desire for food at least -- to teach the capuchins to buy grapes, apples and Jell-O. ''You should really think of a capuchin as a bottomless stomach of want,'' Chen says. ''You can feed them marshmallows all day, they'll throw up and then come back for more.''
The Harvard monkeys were cotton-top tamarins, and the experiments with them concerned altruism. Two monkeys faced each other in adjoining cages, each equipped with a lever that would release a marshmallow into the other monkey's cage. The only way for one monkey to get a marshmallow was for the other monkey to pull its lever. So pulling the lever was to some degree an act of altruism, or at least of strategic cooperation.
The tamarins were fairly cooperative but still showed a healthy amount of self-interest: over repeated encounters with fellow monkeys, the typical tamarin pulled the lever about 40 percent of the time. Then Hauser and Chen heightened the drama. They conditioned one tamarin to always pull the lever (thus creating an altruistic stooge) and another to never pull the lever (thus creating a selfish jerk). The stooge and the jerk were then sent to play the game with the other tamarins. The stooge blithely pulled her lever over and over, never failing to dump a marshmallow into the other monkey's cage. Initially, the other monkeys responded in kind, pulling their own levers 50 percent of the time. But once they figured out that their partner was a pushover (like a parent who buys her kid a toy on every outing whether the kid is a saint or a devil), their rate of reciprocation dropped to 30 percent -- lower than the original average rate. The selfish jerk, meanwhile, was punished even worse. Once her reputation was established, whenever she was led into the experimenting chamber, the other tamarins ''would just go nuts,'' Chen recalls. ''They'd throw their feces at the wall, walk into the corner and sit on their hands, kind of sulk.''
The essential idea was to give a monkey a dollar and see what it did with it. The currency Chen settled on was a silver disc, one inch in diameter, with a hole in the middle -- ''kind of like Chinese money,'' he says. It took several months of rudimentary repetition to teach the monkeys that these tokens were valuable as a means of exchange for a treat and would be similarly valuable the next day. Having gained that understanding, a capuchin would then be presented with 12 tokens on a tray and have to decide how many to surrender for, say, Jell-O cubes versus grapes. This first step allowed each capuchin to reveal its preferences and to grasp the concept of budgeting.
Then Chen introduced price shocks and wealth shocks. If, for instance, the price of Jell-O fell (two cubes instead of one per token), would the capuchin buy more Jell-O and fewer grapes? The capuchins responded rationally to tests like this -- that is, they responded the way most readers of The Times would respond. In economist-speak, the capuchins adhered to the rules of utility maximization and price theory: when the price of something falls, people tend to buy more of it.
Chen next introduced a pair of gambling games and set out to determine which one the monkeys preferred. In the first game, the capuchin was given one grape and, dependent on a coin flip, either retained the original grape or won a bonus grape. In the second game, the capuchin started out owning the bonus grape and, once again dependent on a coin flip, either kept the two grapes or lost one. These two games are in fact the same gamble, with identical odds, but one is framed as a potential win and the other as a potential loss.
How did the capuchins react? They far preferred to take a gamble on the potential gain than the potential loss. This is not what an economics textbook would predict. The laws of economics state that these two gambles, because they represent such small stakes, should be treated equally.
So, does Chen's gambling experiment simply reveal the cognitive limitations of his small-brained subjects? Perhaps not. In similar experiments, it turns out that humans tend to make the same type of irrational decision at a nearly identical rate. Documenting this phenomenon, known as loss aversion, is what helped the psychologist Daniel Kahneman win a Nobel Prize in economics. The data generated by the capuchin monkeys, Chen says, ''make them statistically indistinguishable from most stock-market investors.''
During a recent capuchin experiment that used cucumbers as treats, a research assistant happened to slice the cucumber into discs instead of cubes, as was typical. One capuchin picked up a slice, started to eat it and then ran over to a researcher to see if he could ''buy'' something sweeter with it. To the capuchin, a round slice of cucumber bore enough resemblance to Chen's silver tokens to seem like another piece of currency.
Then there is the stealing. Santos has observed that the monkeys never deliberately save any money, but they do sometimes purloin a token or two during an experiment. All seven monkeys live in a communal main chamber of about 750 cubic feet. For experiments, one capuchin at a time is let into a smaller testing chamber next door. Once, a capuchin in the testing chamber picked up an entire tray of tokens, flung them into the main chamber and then scurried in after them -- a combination jailbreak and bank heist -- which led to a chaotic scene in which the human researchers had to rush into the main chamber and offer food bribes for the tokens, a reinforcement that in effect encouraged more stealing.
Something else happened during that chaotic scene, something that convinced Chen of the monkeys' true grasp of money. Perhaps the most distinguishing characteristic of money, after all, is its fungibility, the fact that it can be used to buy not just food but anything. During the chaos in the monkey cage, Chen saw something out of the corner of his eye that he would later try to play down but in his heart of hearts he knew to be true. What he witnessed was probably the first observed exchange of money for sex in the history of monkeykind. (Further proof that the monkeys truly understood money: the monkey who was paid for sex immediately traded the token in for a grape.)
Posted by Jon Rubin at 10:37 PM | Comments (0) | TrackBack
July 11, 2006
"I'm allergic to microwaves. They release space hamsters into my bloodstream."
Psilocybin scientifically studied, sought sacred psychological symptoms successfully sighted.
In the study, more than 60 percent of subjects described the effects of psilocybin in ways that met criteria for a "full mystical experience" as measured by established psychological scales. One third said the experience was the single most spiritually significant of their lifetimes; and more than two-thirds rated it among their five most meaningful and spiritually significant. Griffiths says subjects liken it to the importance of the birth of their first child or the death of a parent.
Two months later, 79 percent of subjects reported moderately or greatly increased well-being or life satisfaction compared with those given a placebo at the same test session. A majority said their mood, attitudes and behaviors had changed for the better. Structured interviews with family members, friends and co-workers generally confirmed the subjects' remarks. Results of a year-long followup are being readied for publication.
Psychological tests and subjects' own reports showed no harm to study participants, though some admitted extreme anxiety or other unpleasant effects in the hours following the psilocybin capsule. The drug has not been observed to be addictive or physically toxic in animal studies or human populations. "In this regard," says Griffiths, a psychopharmacologist, "it contrasts with MDMA (ecstasy), amphetamines or alcohol."
PGP's tech officer has a relatively strong defense of strong crypto's strength. via
Imagine a computer that is the size of a grain of sand that can test keys against some encrypted data. Also imagine that it can test a key in the amount of time it takes light to cross it. Then consider a cluster of these computers, so many that if you covered the earth with them, they would cover the whole planet to the height of 1 meter. The cluster of computers would crack a 128-bit key on average in 1,000 years.
If you want to brute-force a key, it literally takes a planet-ful of computers. And of course, there are always 256-bit keys, if you worry about the possibility that government has a spare planet that they want to devote to key-cracking.
Now of course, there are other ways to break the system.
They could know something we don't. They could know some fundamental truth about mathematics (like how to factor really fast), some effective form of symmetric cryptanalysis, or something else. They could know about quantum computers, DNA computers, systems based upon non-Einsteinian physics, and so on. Yes, it's possible. But this quickly gets into true paranoid thought.
They could be hacking people's systems.
However, there are things that we know that they *are* doing. One of them is relevant to this particular case. That is work on cracking the passphrases that people use to protect their keys. The cryptography we're using is itself uncrackable, but about 2/3 of the people in the world use a password (not even a passphrase) that directly relates to a pet or loved one.
We know that at least one government has a password cracker that is based upon building a psychometric model of person who owns the key and constructing passphrases on that model.
My old friend and colleague, Drew Gross, who is a forensics expert, has said, "I love crypto; it tells me what part of the system not to bother attacking."
The last bit of evidence we have that suggests that they can't break the crypto is that they are apparently devoting a lot of effort to traffic analysis. Look at what we've learned in the last few months. Listening for keywords is so twentieth century. They're looking at call patterns, message flow, and so on.
The critical threshold of rain, magnets, and unraveling "the mathematical thread of reality" :
In the June issue of the respected journal Nature Physics, he and J. David Neelin, UCLA professor of atmospheric and oceanic sciences, report that the onset of intense tropical rain and magnetism share the same underlying physics.
"We studied properties of that relationship that are also observed in equivalent quantities for systems with 'continuous-phase transitions' like magnets," said Peters, a research scientist with UCLA's Institute of Geophysics and Planetary Physics and a visiting scientist at the Santa Fe Institute.
"The atmosphere has a tendency to move to a critical point in water vapor where the likelihood of rain dramatically increases. The system reaches a point where it's just about to rain; it's highly susceptible. Any additional water vapor can produce a large response."
"Our study showed that absolutely everything we dreamed of finding was actually there," Peters said. "The predictions from critical phenomena showed up in the data. This is a huge step forward in self-organized criticality and critical phenomena. There really is a critical point. We observed the system in a whole range of different water vapors. This is the strongest evidence for any physical self-organized critical system to really have a critical point."
How does a critical threshold point work?
Consider a pile of rice, Peters said. You can add a single grain of rice and measure its effect on the pile. After slowly adding rice grains, at some point you eventually trigger an avalanche; the release is very fast. A similar principle is behind the coin machines you can find in casinos, where it looks as if dropping in one or two quarters will create an avalanche of coins that will come crashing down for you. In fact, it is much more likely that it only looks like the system is at a critical point; you are more likely to lose your quarter.
Imagine that you add one raindrop into a cloud. Like the pile of rice, where adding a single grain can produce an avalanche or nothing at all, or like the coin machine, the one additional raindrop could trigger a huge downpour, but most of the time produces nothing. You can heat a magnet to a point where it loses its magnetization; it no longer has a north and south direction.
"When a magnet is near the critical temperature, a slight perturbation can cause it to switch north and south," Peters said. "When the system reaches the critical point and is so susceptible, a slight change — one more grain of rice, one more coin — can produce a massive response of the system. This phenomenon can be studied using statistical mechanics and critical phenomena."
The sun slowly evaporates water from the oceans, pumping water into the atmosphere. Much of that water vapor is stored and transported in the atmosphere before there is any rain, Neelin noted.
What finally triggers the rain?
Complex interactions among the cloud motions organize the rainfall into clusters in space and a cascade of smaller and larger rain events. And these share the same mathematical structure as systems that physicists have studied.
"Whenever you find different systems that are governed by the same mathematical laws, you are hitting on something fundamental. You have found a thread in the mathematical fabric of reality. This study raises the concept of 'self-organized criticality' to a higher status. It's not just a far-fetched possibility."
Here's an astounding interview with physicist Lawrence Krauss, whom you might recall from The Physics of Star Trek. via
We knew the answer. There was a symmetry and the number had to be exactly zero. Well, what have we discovered? There appears to be this energy of empty space that isn't zero! This flies in the face of all conventional wisdom in theoretical particle physics. It is the most profound shift in thinking, perhaps the most profound puzzle, in the latter half of the 20th century. And it may be the first half of the 21st century, or maybe go all the way to the 22nd century. Because, unfortunately, I happen to think we won't be able to rely on experiment to resolve this problem. When we look out at the universe, if this dark energy is something that isn't quite an energy of empty space but its just something that's pretending to be that, we might measure that it's changing over time.
Then we would know that the actual energy of empty space is really zero but this is some cockamamie thing that's pretending to be energy of empty space. And many people have hoped they'd see that is because then you wouldn't need quantum gravity, which is a theory we don't yet have, to understand this apparent dark energy. Indeed, one of the biggest failures of string theory's many failures, I think, is it never successfully addressed this cosmological constant problem. You'd think if you had a theory of quantum gravity, it would explain precisely what the energy of empty space should be. And we don't have any other theory that addresses that problem either! But if this thing really isn't vacuum energy, then it's something else, then you might be able to find out what it is, and learn and do physics without having to understand quantum gravity.
Right now it's clear that what we really need is some good new ideas. Fundamental physics is really at kind of a crossroads. The observations have just told us that the universe is crazy, but hasn't told us what direction the universe is crazy in. The theories have been incredibly complex and elaborate, but haven't yet made any compelling inroads. That can either be viewed as depressing or exciting. For young physicists it's exciting in the sense that it means that the field is ripe for something new.
The great hope for particle physics, which may be a great hope for quantum gravity, is the next large particle accelerator. We've gone 30 years without a fundamentally new accelerator that can probe a totally new regime of the sub-atomic world. We would have had it if our legislators had not been so myopic. It's amazing to think that if they hadn't killed the superconducting Super Collider it would have been already been running for ten years.
The Large Hadron Collider is going to come on-line next year. And one of two things could happen: It could either reveal a fascinating new window on the universe and a whole new set of phenomena that will validate or refute the current prevailing ideas in theoretical particle physics, supersymmetry etc, or it might see absolutely nothing. I'm not sure which I'm rooting for.
But what is intriguing to me is that while everything is consistent with the simplest models, there's one area where there's a puzzle. On the largest scales, when we look out at the universe, there doesn't seem to be enough structure — not as much as inflation would predict. Now the question is, is that a statistical fluke?
That is, we live in one universe, so we're a sample of one. With a sample of one, you have what is called a large sample variance. And maybe this just means we're lucky, that we just happen to live in a universe where the number's smaller than you'd predict. But when you look at CMB map, you also see that the structure that is observed, is in fact, in a weird way, correlated with the plane of the earth around the sun. Is this Copernicus coming back to haunt us? That's crazy. We're looking out at the whole universe. There's no way there should be a correlation of structure with our motion of the earth around the sun — the plane of the earth around the sun — the ecliptic. That would say we are truly the center of the universe.
The new results are either telling us that all of science is wrong and we're the center of the universe, or maybe the data is imply incorrect, or maybe it's telling us there's something weird about the microwave background results and that maybe, maybe there's something wrong with our theories on the larger scales.
Posted by Jon Rubin at 09:45 PM | Comments (0) | TrackBack
July 10, 2006
"You see the fascinating thing about Ares is that he’s completely incompetent. [...] He’s wounded by one of Odysseus’s drinking buddies during the Iliad. Athena knocks him out with a rock at one point."
Some advice for someone about to read Neal Stephenson's novel Quicksilver.
Don't read this if you haven't read Cryptonomicon and plan to read it, as there are a number of spoilers meant as refreshers for people who read the novel long ago and don't care to re-read.
Don't read this if you're really fragile about spoilers and wouldn't want to know something about Quicksilver like "This one character only gets that one chapter from his/her point of view, so read carefully." I'm revealing so little of the Baroque Cycle as for it to be negligible, and rather cryptically at that.
You should be made aware now, at the very beginning of your read, that Neal Stephenson does not play nice.
Quicksilver ends a dozen years before it begins. The chronology of the trilogy is so, ahem, confused, that even volume 2 ends before volume 1 began. Volume 3 finally catches up with the end of the beginning of Quicksilver (got that?), and then goes another year or so forward in time.
When you've read the three novels you're going to want to go back and reread the beginning of Quicksilver again. Why? As I already said, Neal Stephenson does not play nice: the series ends without Enoch and Daniel having another face-to-face conversation after the one that begins Quicksilver. Stephenson intentionally denies the reader that—he has Daniel think several times "Boy, I really need to sit down and have another chat with Enoch, I'll have to do that when I get back to Boston" and then nothing. So you'll want to read that beginning carefully. In many ways, it has to function as the chronological end-piece of the series. Sure, events go on another year into the future, but there's not another clear statement of principles. I mean, there is a world-class conversation between Leibniz and Newton that must have taken Stephenson months to write. It is as if he channels the geniuses (geniii?) themselves and their dialogue is the crowning moment of the series and the philosophical centerpiece of volume 3, The System of the World....but that conversation, however brilliant, ends in a draw. Also, there's not another segment from Enoch Root's point of view, after the beginning of Quicksilver. That's important, considering that "Enoch" is the first word of the entire trilogy. Though...occulted...Enoch is somewhere behind the scenes in all the storylines.
Until you're halfway through the final volume of the trilogy you'll think Quicksilver has the worst possible ending of the literally dozens Stephenson could have chosen. After you've read the majority of The System of the World you'll realize there is no other way Stephenson could have ended Quicksilver.
You're also going to want to try to remember some key leftover plot threads from Cryptonomicon:
Rudy Hacklheber's family was friends with Enoch Root and there were so many connections he'd have to "write a whole fucking book" to explain them. In truth, more like three.
There were a bunch of golden plates with holes punched out of them, which Rudy stole from the Nazis, and which sank in the sub that was salvaged in the present-day storyline. These plates were in boxes labeled "NIZ-ARCH." This will make sense after The Confusion.
In one weird scene, Enoch Root died in a hospital from Nazi gunfire. Before he dies, he tells Rudy to get his cigar box. Then he dies on the operating table. Rudy comes back with the cigar box, and makes everyone leave the room. A few minutes later, Enoch walks out of the room, alive.
Bobby Shaftoe, the marine, he was almost killed at one point, but Enoch saved him. He doesn't remember how, exactly, but he thinks it has something to do with the box...the clearest it gets is in a dream when Bobby hallucinates he's on a sub:
A lot of the other speaking tubes have ruptured now and screaming comes from most of them; Root has to lean close to in order to shout into Bobby's ear. Shaftoe takes advanatge of it to reach over and grab for the cigar box, which contains the stuff he wants: not morphine. Something better than morphine. Morphine is to the stuff in the cigar box what a Shanghai prostitute is to Glory.
The box flies open and blinding light comes out of it. Shaftoe covers his face. The salted and preserved body parts suspended from the ceiling tumble into his lap and begin to writhe, reaching out for other parts, assembling themselves into living bodies. Mikulski comes back to life, aims his Vickers at the ceiling of the U-boat, and cuts an escape hatch. Intsead of black water, golden light rushes through.
You'll probably want to reread the key passage in Cryptonomicon (that's a pun, see...it's the key passage in the way of a keystone, but also a key as in it decodes the book's message)...it's an amazing bit of writing concerning philosophy, geekiness, and mythology. (Search down til the word "occult" and read down from there until Enoch goes to sleep.)
There's one more Cryptonomicon segment worth rereading, the conversation between Waterhouse and Turing and Hacklheber at the beginning...it's all about Leibniz, who increasingly becomes the focus of the follow-up trilogy. Pretty much all of this chapter is key for understanding Quicksilver. (If you want you can skip down to "Quite a few of these men would pretend", read down to "Soon it became clear what Alan meant", then skip the Hindenburg crash and pick back up at "Did you solve the problem?" until "Just noise in the neurons.")
Finally, the most important source of information for someone reading Quicksilver is the wiki of Quicksilver annotations. You can even get the annotations as a stylin' PDF and print them out to read aside the book, feel all intellectual like you're reading a really complex book like Ulysses or something and not overwrought, operatic, historical sci-fi.
Posted by Jon Rubin at 10:04 PM | Comments (0) | TrackBack
July 09, 2006
"It was a six hour bus ride with a lot of stops. May I have some water please?" "Sorry, my parents aren't home. But you could use the hose out front." "Delightful!"
Trying to make sense of Dan Simmon's Ilium-Olympos duology, I checked out the Wikipedia page on Calabi-Yau manifolds, which has to be the most abstruse entry on the entire site. I mean, is this even English?
A Calabi-Yau manifold is a Kähler manifold with a vanishing first Chern class. A Calabi-Yau manifold of complex dimension n is also called a Calabi-Yau n-fold. The mathematician Eugenio Calabi conjectured in 1957 that all such manifolds admit a Ricci-flat metric (one in each Kähler class), and this conjecture was proved by Shing-Tung Yau in 1977 and became Yau's theorem. Consequently, a Calabi-Yau manifold can also be defined as a compact Ricci-flat Kähler manifold.
Equivalently one may define a Calabi-Yau n-fold as a manifold with an SU(n) holonomy. Yet another equivalent condition is that the manifold admit a global nowhere vanishing holomorphic (n,0)-form.
The first Chern class vanishes if and only if the canonical bundle is trivial, which in turn is the case if and only if the canonical class is the zero class. While the Chern class fails to be well-defined for singular Calabi-Yau's, the canonical bundle and canonical class may still be defined and so may be used to extend to definition of a smooth Calabi-Yau manifold to a possibly singular Calabi-Yau variety.
The Talk page for the Calabi-Yau Wikipedia entry is hilarious. Regular people complain that not only does the entry not make any sense to the layman, but neither do any of the other entries it links to. Physicists, in turn, do their best to try to explain this stuff simply but can't do better than the following, which makes no more sense to me than the excerpt above:
A Calabi-Yau manifold is a particular type of Kähler manifold, which is a manifold which carries a complex structure and a Hermitian structure which are compatible in each other in a technical way. For a Kähler manifold to be Calabi-Yau manifold, its curvature form must be an exact differential, which also implies that the trace of its curvature form vanishes, according to a famous result by Calabi and Yau.
Supposedly Apple's got a new logic board available for MacBook Pros (again I wonder, should it be MacBooks Pro?).
Jack Abramoff visited the White House more often than they had previously admitted. via
The first set of documents released to Judicial Watch on May 10 indicated that Abramoff only made two visits to the White House on March 6, 2001 and January 20, 2004. The new documents show an additional seven data entries concerning Abramoff appointments on the following dates: March 1, 2001; March 6, 2001; April 20, 2001; May 9, 2001; May 17, 2001; December 7, 2001; and December 10, 2001. According to the cover letter accompanying the documents, “The…data reflect appointments involving Jack Abramoff, but do not necessarily reflect actual visits to the White House Complex.”
Ice spoon: its time has come
Bacon cereal: its time will never come.
Posted by Jon Rubin at 07:53 PM | Comments (0) | TrackBack
July 08, 2006
"All the changes, all the permutations of reality that we see are expressions of the purposeful growing and unfolding of this single entelechy; it is a plant, a flower, an opening rose. It is a humming hive of bees. It is music, a kind of singing."
OMG someone actually submitted a comment to my blog post yesterday! There's some bonus irony too, since my last post's title was an allusion to my dearth of readers...
For those not keeping score at home, that would be the twentieth comment I've gotten in over a year and a half of blogging and over three hundred and fifty posts, and only the tenth comment from someone I don't know in meatspace.
Ryan feels that the shorter blog posts I've been publishing of late are preferable to the voluminous ones I once tended towards, and I am somewhat in agreement. In fact, one of my goals for this summer is to redesign this blog so that I can migrate to posting one link at a time.
However, I'm also a contrary person by nature, so here's a really long post just for the hell of it =P
No [via] citations since these links are stale (most of 'em have been mouldering in NetNewsWire since, like, April) and finding the proper attributions would take hours.
Digs in the Norte Chico valleys are rewriting Peruvian history by demonstrating that the region had a highly-developed culture two millennia earlier than previously thought. Hell, world history—these pyramid-builders were already established as a civilization 500 years before the first Egyptian pyramid was built. There's a good, related Horizon documentary about the ruins of Caral called "Hidden Pyramids of Peru" by the National Geographic Channel and "The Lost Pyramids of Caral" by the BBC.
Archaeologists used radiocarbon dating to chart the rise and fall of the little known culture, which reigned over three valleys north of Lima.
The society, whose heyday ran from 3000 to 1800BC, built ceremonial pyramids and complex irrigation systems.
The find casts doubt on the idea that Andean civilisation began by the sea.
The ancient society had a close inter-dependent relationship with nearby coastal settlements, which were uncovered much earlier by archaeologists.
The people of the inland Norte Chico area grew cotton, which they traded with their coastal neighbours in exchange for fish. In turn, the coast dwellers used the cotton to make their fishing nets.
According to one Biblical scholar/philologist, there's no evidence of cannabis in the Bible. I remain zetetical, as the research seems a bit sloppy. The scholar cites the correct passage (Exodus 30:23), but he's supposed to be rebutting cannabis as an ingredient in the anointing oil, not in the sacred incense...
1. There is no credible evidence that the etymology of cannabis (Latin "hemp") is connected to Hebrew קנה בשם qeneh bosem (Exodus 30:23), literally "reed of sweet spice."
2. The best guess as to the identity of qeneh bosem, an ingredient in the incense used in the tabernacle, is that it was lemon grass (Cymbopogon citratus). (See the entry in Immanuel Löw's Flora der Juden, 1924-34.) Nobody knows for sure.
Zorbing—that new sport where you strap yourself into an inflatable plastic ball and roll down a hill—is...how shall I phrase this as to maximize puntential?...causing a revolution in recreation.
Mr Akers explained that there are a number of reasons New Zealanders why have developed an attraction to developing these types of activities.
"We're so far away from anywhere that we've really had to make our own fun," he said.
"Also, if you injure yourself, then the government is going to pay for you to not only get back on your feet, but they're going to rehabilitate you and get you back into the workplace as well.
"This means that we have a non-litigious society, and so a lot of things start up that possibly would not be able to start up anywhere else in the world."
How-to: cure asthma with hookworms
This is my personal account of curing my asthma and hayfever by deliberately infesting myself with the intestinal parasite hookworm.
It isn't for the faint hearted and for some should not be read while eating.
It involves a great deal of research, a trip to Cameroon and a lot of barefoot walking in open air latrines in west Africa.
Covering the basics, some Australian scientists have discovered that vitamin A decides gender.
The cells that eventually turn into either eggs or sperm – known as germ cells – are identical in male and female embryos.
"Whether a germ cell develops into an egg or a sperm depends on the time at which meiosis begins," Professor Koopman said.
"In females, meiosis begins before birth and eggs are produced, whereas in males, meiosis begins after birth and the result is sperm."
Professor Koopman and his team found that retinoic acid, a derivative of Vitamin A, causes germ cells in female embryos to begin meiosis, leading to the production of eggs.
They also discovered an enzyme present in male embryos that wipes out retinoic acid and so suppresses meiosis until after birth, resulting in sperm production.
If you have Mac OS X Tiger, maybe you ought to be using Automator. I always felt they shoulda stuck with the development code name and just called it Pipe.
Open your Applications folder and look for Automator. You’ll recognize it by the icon of a robot carrying what appears to be a bazooka. It seems that many have started to call our little robotic friend “Otto.” And no, that is not a bazooka in his hand. It is, in fact, a pipe—representing the power of the Unix pipeline. Those of you with a better understanding of Unix than I have will understand what that means.
Initially, I wasn’t too impressed with the ability to save workflows as plug-ins, but I have changed my mind. When fellow editor Eric Blair saw a draft of this article, he pointed out that saving workflows as Finder plug-ins allows users to create their own contextual menu items. Imagine being able to right click files and upload them to a specific server, or create disk images with specific settings by working in conjunction with DropDMG (a utility from ATPM’s publisher).
This write-up of some recent zoological discoveries in an Israeli cave sounds like the exposition to a bad horror flick:
The cave, which has been dubbed the Ayalon Cave, is "unique in the world," said Prof. Amos Frumkin of the Hebrew University Department of Geography. This is due mainly to its isolation from the outside world, since the cave's surface is situated under a layer of chalk that is impenetrable to water. The cave, with its branches, extends over some 2½ kilometers, making it Israel's second largest limestone cave.
The invertebrate animals found in the cave – four seawater and freshwater crustaceans and four terrestial species – are related to but different from other, similar life forms known to scientists. The species have been sent to biological experts in both Israel and abroad for further analysis and dating. It is estimated that these species are millions of years old. Also found in the cave were bacteria that serve as the basic food source in the ecosystem.
"The eight species found thus far are only the beginning" of what promises to be "a fantastic biodiversity," said Dr. Hanan Dimentman of the Hebrew University Alexander Silberman Institute of Life Sciences, another of the researchers involved in the project. He said that he expects further exploration to reveal several other unique life forms.
The animals found there were all discovered live, except for a blind species of scorpion, although Dr. Dimentman is certain that live scorpions will be discovered in further explorations and also probably an animal or animals which feed on the scorpions.
The lake is part of the Yarkon-Taninim aquifer, one of Israel's two aquifers, yet is different in temperature and chemical composition from the main waters of the aquifer. The lake's temperature and salinity indicates that its source is deep underground.
Dentistry is old. Real old.
Primitive dentists drilled nearly perfect holes into live but undoubtedly unhappy patients between 5500 B.C. and 7000 B.C., an article in Thursday's journal Nature reports. Researchers carbon-dated at least nine skulls with 11 drill holes found in a Pakistan graveyard.
That means dentistry is at least 4,000 years older than first thought — and far older than the useful invention of anesthesia.
This was no mere tooth tinkering. The drilled teeth found in the graveyard were hard-to-reach molars. And in at least one instance, the ancient dentist managed to drill a hole in the inside back end of a tooth, boring out toward the front of the mouth.
The holes went as deep as one-seventh of an inch (3.5 millimeters).
Researchers figured that a small bow was used to drive the flint drill tips into patients' teeth. Flint drill heads were found on site. So study lead author Roberto Macchiarelli, an anthropology professor at the University of Poitiers, France, and colleagues simulated the technique and drilled through human (but no longer attached) teeth in less than a minute.
Researchers were impressed by how advanced the society was in Pakistan's Baluchistan province. The drilling occurred on ordinary men and women.
The dentistry, probably evolved from intricate ornamental bead drilling that was also done by the society there, went on for about 1,500 years until about 5500 B.C., Macchiarelli said. After that, there were no signs of drilling.
Here's a nice mathy page on Phi, the golden ratio.
Bertrand Russell, infinity, and the Tristram Shandy paradox of the slow autobiographer
Sterne writes about Tristram Shandy as an individual committed to writing an autobiography. However, he is so slow that it takes him one year in order to complete only one day. This means that the most recent event that could be recorded is the day that occurred one year ago. As Shandy writes an additional day, it takes him an additional year to complete the events of that day. Russell uses this example and believes that an actual infinite can be achieved through successive addition only if Shandy has an infinite number of days to complete it.
Craig responds to Russell that the problem with this argument seems to be that while an infinite number of years is a necessary condition of recording an infinite number of days at the rate of one day per year, it is not a sufficient condition. What is also needed is that the days and years be arranged in a certain way such that every day is succeeded by a year in which to record it. But then it will be seen that Tristram Shandy's task is inherently paradoxical; the absurdity lies not in the infinity of the past but in the task itself.(7)
Craig continues and claims that instead of Shandy writing forever and catching up on history, he would eventually be infinitely far behind.
"Kepler would be pleased"—John Baez's tour de force post on math and neo-Riemannian music theory:
When Tom first mentioned "neo-Riemannian theory", I thought this was some bizarre application of differential geometry to music. But no - we're not talking about the 19th-century mathematician Bernhard Riemann, we're talking about the 19th-century music theorist Hugo Riemann!
Based on the work on Euler - yes, the Euler - Hugo Riemann introduced diagrams called "tone nets" to study the network of relations between similar chords.
Apparently Riemann's ideas have caught on in a big way. Monzo says that "use of lattices is endemic on internet tuning lists", as if they were some sort of infectious disease.
Dysart seems more gung-ho about it all. The "donuts" he mentions arise when you curl up tone nets by identifying notes that differ by an octave. He has some nice pictures of them!
In neo-Riemannian theory, people like Lewin and Hyer started extending Riemann's ideas by using group theory to systematize operations on chords. The best easy introduction to this is Fiore's paper "Music and mathematics". Here you can read about math lurking in the music of Elvis and the Beatles! Or, if you're more of a highbrow sort, see what he has to say about Hindemith and Liszt's "Transcendental Etudes". And if you like doughnuts and music, you'll love the section where he explains how Beethoven's Ninth traces out a systematic path in a torus-shaped tone net!
The transposition-inversion group has 24 elements. Mathematicians call it the 24-element "dihedral group", since it consists of the symmetries of a regular 12-sided polygon where you're allowed to rotate the polygon (transposition) and also flip it over (inversion). I hope you see that this geometrical picture is just a way of visualizing the 12 notes.
You should be left wondering why P, L, and R generate the group of all transformations of triads that commute with transposition and inversion - and why this group, like the transposition-inversion group itself, has exactly 24 elements!
It turns out some of this has a simple explanation, which has very little to do with the details of triads or even the 12-note scale.
Imagine a scale with n equally spaced notes. Transpositions and inversions will generate a group with 2n elements. Let's call this group G. If you take any "sufficiently generic" chord in our scale, G will act on it to give a set S consisting of 2n different chords. Then it's a mathematical fact that the group of permutations of S that commute with all transformations in G will be isomorphic to G! So, it too will have 2n elements.
The pretty math I've just described only captures a microscopic portion of what makes music interesting. It doesn't, for example, have anything to say about what makes some intervals more dissonant than others. As Pythagoras noticed, simple frequency ratios like 3/2 or 4/3 make for less dissonant chords than gnarly fractions like 1259/723. The equal tempered tuning system, where the basic frequency ratio is 21/12, would have made Pythagoras roll in his grave! Advocates of other tuning systems say these irrational frequency ratios are driving us crazy, making wars break out and plants wilt - but there's an unavoidable conflict between the desire for simple ratios and the desire for evenly spaced notes, built into the fabric of mathematics and music. Every tuning system is thus a compromise. I would like to understand this better; there's bound to be a lot of nice number theory here.
More generally: if you give me any voice leading between C major and E minor, I can give you an exactly analogous voice leading between D major and F# minor, or C minor and Ab major, etc. So "neo-Riemannian" progressions identify a class of harmonic progressions (functions between unordered collections of points on the circle) that are interesting from a voice leading perspective. (They identify pairs of chord progressions that can be linked by the same voice leadings, to within rotation and reflection.)
Posted by Jon Rubin at 08:53 PM | Comments (1) | TrackBack
July 07, 2006
"Both our viewers must be thrilled."
I should probably upgrade VoodooPad but I'm having difficulty believing it's worth ten bucks.
This FAQ for Trauma Center, a Nintendo DS game, has been handy a few times now...
There are plenty of VPN client front-ends for OS X, like IPSecuritas and VaporSec, but I'm having a lot of trouble locating a VPN server solution short of installing Mac OS X Server edition.
Yeah, another truncated post...I really do have dozens of links I should be posting...
Posted by Jon Rubin at 11:28 PM | Comments (1) | TrackBack
July 06, 2006
"A few honest men are better than numbers."
Cheney expects a bad economy if you look at his financial records: via
According to Tom Blackburn of the Palm Beach Post, Cheney has invested heavily in "a fund that specializes in short-term municipal bonds, a tax-exempt money market fund and an inflation protected securities fund. The first two hold up if interest rates rise with inflation. The third is protected against inflation."
Cheney has dumped another (estimated) $10 to $25 million in a European bond fund which tells us that he is counting on a steadily weakening dollar.
Recently, the King's Table was found buried under Westminster Palace. via
They were buried beneath the floor of Westminster Hall, apparently as a symbol of the return of royal power after the fall of the Commonwealth. When Cromwell came to power the table was removed from the Palace and broken up to mark the destruction of the monarchy.
Nintendo's birthday present for Bush was a DS Lite and a copy of Brain Age: Train Your Brain in Minutes a Day, a title oft suggested for Alzheimer sufferers.
Training tests include categories like math, reading and memorization. Try it for a few days and watch your score improve.
For a change, and by popular demand, Microsoft has ceded a format war and will include an OpenDocument format plug-in in the next version of Office in addition to supporting their own new "open" standard.
Posted by Jon Rubin at 10:46 PM | Comments (0) | TrackBack
July 05, 2006
~The galaxy's the body, sun is the heart, and the black hole's the brain~
The original story of Hamlet is way darker than the Shakespeare:
Afraid of being overheard by some eavesdropper, he at first resorted to his usual imbecile ways, and crowed like a noisy cock, beating his arms together to mimic the flapping of wings. Then he mounted the straw and began to swing his body and jump again and again, wishing to try if aught lurked there in hiding. Feeling a lump beneath his feet, he drove his sword into the spot, and impaled him who lay hid. Then he dragged him from his concealment and slew him. Then, cutting his body into morsels, he seethed it in boiling water, and flung it through the mouth of an open sewer for the swine to eat, bestrewing the stinking mire with his hapless limbs. Having in this wise eluded the snare, he went back to the room. Then his mother set up a great wailing and began to lament her son's folly to his face but he said: "Most infamous of women! dost thou seek with such lying lamentations to hide thy most heavy guilt? Wantoning like a harlot, thou hast entered a wicked and abominable state of wedlock, embracing with incestuous bosom thy husband's slayer. . ." With such reproaches he rent the heart of his mother and redeemed her to walk in the ways of virtue.
When Fengo returned, nowhere could he find the man who had suggested the treacherous espial. . . Amleth, among others, was asked in jest if he had come on any trace of him, and replied that the man had gone to the sewer, but had fallen through its bottom and been stifled by the floods of filth, and that he had then been devoured by the swine that came up all about that place. This speech was flouted by those who heard; for it seemed senseless, though really it expressly avowed the truth.
Covered with filth, he entered the banquet-room where his own obsequies were being held, and struck all men utterly aghast, rumour having falsely noised abroad his death. At last terror melted into mirth, and the guests jeered and taunted one another, that he, whose last rites they were celebrating as though he were dead, should appear in the flesh. When he was asked concerning his comrades, he pointed to the sticks he was carrying, and said, "Here is both the one and the other." This he observed with equal truth and pleasantry. . . for it pointed at the weregild of the slain as though it were themselves.
Thereon, wishing to bring the company into a gayer mood, he joined the cupbearers, and diligently did the office of plying the drink. Then, to prevent his loose dress hampering his walk, girded his sword upon his side, and purposely drawing it several times, pricked his fingers with its point. The bystanders accordingly had both sword and scabbard riveted across with an iron nail. Then, to smooth the way the more safely to his plot, he went to the lords and plied them heavily with draught upon draught, and drenched them all so deep in wine, that their feet were made feeble with drunkenness, and they turned to rest within the palace, making their bed where they had reveled . . .
So he took out of his bosom the stakes he had long ago prepared, and went into the building, where the ground lay covered with the bodies of the nobles wheezing off their sleep and their debauch. Then, cutting away its supports, he brought down the hanging his: mother had knitted, which covered the inner as well as the outer walls of the hall. This he flung upon the snorers, and then applying the crooked stakes, he knotted and bound them in such insoluble intricacy, that not one of the men beneath, however hard he might struggle, could contrive to rise. After this he set fire to the palace. The flames spread, scattering the conflagration far and wide. It enveloped the whole dwelling, destroyed the palace, and burnt them all while they were either buried in deep sleep or vainly striving to arise.
Then he went to the chamber of Fengo, who had before this been conducted by his train into his pavilion; plucked up a sword that chanced to be hanging to the bed, and planted his own in its place. Then, awakening his uncle, he told him that his nobles were perishing in the flames, and that Amleth was here, armed with his old crooks to help him, and thirsting to exact the vengeance, now long overdue, for his father's murder. Fengo, on hearing this, leapt from his couch, but was cut down while, deprived of his own sword, he strove in vain to draw the strange one. . . O valiant Amleth, and worthy of immortal fame, who being shrewdly armed with a feint of folly, covered a wisdom too high for human wit under a marvellous disguise of silliness and not only found in his subtlety means to protect his own safety, but also by its guidance found opportunity to avenge his father. By this skillful defence of himself, and strenuous revenge for his parent, "he has left it doubtful whether we are to think more of his wit or his bravery.
Reading Dan Simmons' excellent novel Ilium the other day, I ran across a bit of mythological trivia. Before sailing to Troy, Agamemnon ran into some trouble. The winds were not favorable. To sate the gods he sacrificed a girl, Iphigeneia, who is usually described as his daughter. In fact, Aeschylus' Oresteia trilogy has this sacrifice as the tragic downfall of Agamemnon; his wife Clytemnestra murders him out of a mother's sense of vengeance. But an alternate telling of the story has that Iphigeneia is the daughter of Helen. Yeah, Menelaus' Helen. Paris' Helen. Helen of Troy. See, when Helen was a young girl, Theseus came a-raiding and a-pillaging. Theseus...of the Minotaur, and the riddle of Theseus' ship—the legendary (as in not necessarily real) founder of Athens and unifier of Attica. Theseus decided to rape Helen, who was already a blossoming young demi-goddess (Helen's mother was Leda, who got raped by Zeus). For some reason, Leda made Helen give the resultant child to Clytemnestra—Helen's sister. IMO, all these incestuous familial ties add several layers to the stories. Would Helen have run off with Paris if she knew that it would lead to her brother-in-law killing her daughter?
Posted by Jon Rubin at 11:30 PM | Comments (0) | TrackBack
July 04, 2006
"Freedom, high-day! high-day, freedom! freedom, high-day, freedom!"
Some researchers in the UK have figured out how to attach prosthetics to the skeleton that emerge from the skin without risking infection. via
The technique, called Intraosseous Transcutaneous Amputation Prosthesis (ITAP), involves securing a titanium rod directly into the bone. The metal implant passes through the skin and the artificial limb can be directly attached to it.
One of these days, I have literally dozens of links to post...really! I swear.
Posted by Jon Rubin at 10:39 PM | Comments (0) | TrackBack
July 03, 2006
"Do not say a little in many words, but a great deal in a few."
The Babylonians knew about "Pythagorean" triplets and the "Pythagorean" theorem almost 4,000 years ago, according to a tablet known as Plimpton 322:
The numbers in the first column are interesting since each is a perfect square and subtracting one from each leaves a perfect square. Consider, for instance, line 11. The number 1:33:45 represents 1 + 33/60 + 45/3600 = 1 + 9/16 = 25/16 which is the square of 5/4. One less than 25/16 is 9/16, the square of 3/4. The second and third entries in this row represent these fractions: 45 represents 45/60 = 3/4 and 1:15 represents 1 + 15/60 = 5/4. (Or perhaps 45 represents 45 and 1:15 represents 75 in which case these two entries are proportional to the fractions.)
For another example, consider row 5. 1:48:54:01:40 represents 1 + 48/60 + 54/3600 + 1/216000 + 40/12960000 = 1 + 4225/5184 = 9409/5184, which is the square of 97/72. And 4225/5184 is the square of 65/72. The second and third entries in row 5 are 1:05 representing 65, and 1:37 representing 97. Nearly always, the second and third entries aren't equal to the square roots, but just proportional to them.
This table is usually considered in relation to Pythagorean triples. In that interpretation, the second column is a, one side of a right triangle or the width of a rectangle, and the third column is c, the hypotenuse of the right triangle or the diagonal of the rectangle, and the other side of the triangle or rectangle, b, doesn't appear on the table. In this interpretation the first column is then (c/b)2 = 1 + (a/b)2.
The Old Babylonians knew the Pythagorean theorem (better called the rule of the right triangle for them since there's no evidence that they had a proof; Gillings calls the term "the Pythagorean theorem" a true mumpsimus), since there are examples of its use in various problems of the period. Along with the headings of the second and third columns, that justifies believing that this table relates to Pythagorean triples and right triangles.
Some historians have noticed that (1) each first column entry is the square of the cosecant of an angle of a right triangle, and (2) the associated angles are roughly one degree apart. So they have suggested that this is a trigonometric table of squares of cosecants for 45° down to 30°. This would be the earliest instance of cosecants by millennia, and the earliest instance of a trigonometric function by over a thousand years (the first trig function being the chord of an angle). It would also be the earliest instance of degree measurement by over a thousand years. In other words, that's a bold claim. A weaker claim is that the table was constructed to make the first column uniformly decreasing.
....sorry, that's it. I really meant to post more but ran out of time...
Posted by Jon Rubin at 10:45 PM | Comments (0) | TrackBack
July 02, 2006
"I can not have an aide who will not look up. You will be forever walking into things."
The Sci Fi Channel, for the past few weeks, has been incessantly airing promos for its annual July 4th weekend Twilight Zone marathon. Every time the promos air, my ears perk up, because they begin something like: "Between the darkness and the light there is the gray," and it always makes me think of Babylon 5 and the greeting of the Minbari Council of 9:
"Summoned, I come. In Valen's name I take the place that has been prepared for me. I'm Grey. I stand between the candle and the star. We are Grey. We stand between the darkness .. and the light."
I was just watching an episode in that TZ marathon, called "It's a Good Life." I'd never seen it before (though of course I'd heard of it and seen a knock-off or two), and it's one of the better episode of the Twilight Zone. A capricious young boy with unexplained omniscience and omnipotence terrorizes a small town. Anyway...
The boy is played by "Billy Mumy" who would grow up to play the Minbari diplomat/warrior Lennier from Babylon 5.
And yes, that's my entire blog post for today.
Posted by Jon Rubin at 10:22 PM | Comments (0) | TrackBack
July 01, 2006
"A foolish expedient for making idle people believe they are doing something clever when they are only wasting their time."
En lieu of a real post with content, here're some more Wikipedia links. This time, the topic, rather than being research for a creative writing project, is the role of hard math in public-private key cryptography.
1. Alice and Bob agree on a finite cyclic group G and a generating element g in G. (This is usually done long before the rest of the protocol; g is assumed to be known by all attackers.) We will write the group G multiplicatively.
2. Alice picks a random natural number a and sends ga to Bob.
3. Bob picks a random natural number b and sends gb to Alice.
4. Alice computes (gb)a.
5. Bob computes (ga)b.
Both Alice and Bob are now in possession of the group element gab which can serve as the shared secret key. The values of (gb)a and (ga)b are the same because groups are power associative.
Jaina mathematicians in ancient India first conceived of logarithms from around the 2nd century BC. By the 2nd century AD, they performed a number of operations using logarithmic functions to base 2, and by the 8th century, Virasena described logarithms to bases 2, 3 and 4. By the 13th century, logarithmic tables were produced by Muslim mathematicians.
In the 17th century, Joost Bürgi, a Swiss clockmaker in the employ of the Duke of Hesse-Kassel, first discovered logarithms as a computational tool; however he did not publish his discovery until 1620. The method of logarithms was first publicly propounded in 1614, in a book entitled Mirifici Logarithmorum Canonis Descriptio, by John Napier, Baron of Merchiston in Scotland, four years after the publication of his memorable discovery. This method contributed to the advance of science, and especially of astronomy, by making some difficult calculations possible. Prior to the advent of calculators and computers, it was used constantly in surveying, navigation, and other branches of practical mathematics. It supplanted the more involved prosthaphaeresis, which relied on trigonometric identities, as a quick method of computing products. Besides their usefulness in computation, logarithms also fill an important place in the higher theoretical mathematics.
At first, Napier called logarithms "artificial numbers" and antilogarithms "natural numbers". Later, Napier formed the word logarithm, a portmanteau, to mean a number that indicates a ratio: λόγος (logos) meaning proportion, and αριθμoς (arithmos) meaning number. Napier chose that because the difference of two logarithms determines the ratio of the numbers for which they stand, so that an arithmetic series of logarithms corresponds to a geometric series of numbers.
In public key cryptography, the private key is kept secret, while the public key may be widely distributed. In a sense, one key "locks" a lock; while the other is required to unlock it. It should not be possible to deduce the private key of a pair given the public key, and in high quality algorithms no such technique is known.
An analogy which can be used to understand the advantages of an asymmetric system is to imagine two people, Alice and Bob, sending a secret message through the public mail. In this example, Alice has the secret message and wants to send it to Bob, after which Bob sends a secret reply.
With a symmetric key system, Alice first puts the secret message in a box, and then locks the box using a padlock to which she has a key. She then sends the box to Bob through regular mail. When Bob receives the box, he uses an identical copy of Alice's key (which he has somehow obtained previously, maybe by a face-to-face meeting) to open the box, and reads the message. Bob can then use the same padlock to send his secret reply.
In an asymmetric key system, Bob and Alice have separate padlocks. First, Alice asks Bob to send his open padlock to her through regular mail, keeping his key to himself. When Alice receives it she uses it to lock a box containing her message, and sends the locked box to Bob. Bob can then unlock the box with his key and read the message from Alice. To reply, Bob must similarly get Alice's open padlock to lock the box before sending it back to her.
The critical advantage in an asymmetric key system is that Bob and Alice never need send a copy of their keys to each other. This substantially reduces the chance that a third party (perhaps, in the example, a corrupt postal worker) will copy a key while it is in transit, allowing said third party to spy on all future messages sent between Alice and Bob. In addition, if Bob were to be careless and allow someone else to copy his key, Alice's messages to Bob would be compromised, but Alice's messages to other people would remain secret, since the other people would be providing different padlocks for Alice to use.
Mathematicians sometimes use the notion of "polynomial time on the length of the input" as a definition of a "fast" computation, as opposed to "super-polynomial time", which is anything slower than that. Exponential time is one example of a super-polynomial time.
The complexity class of decision problems that can be solved on a deterministic sequential machine in polynomial time is known as P. The class of decision problems that can be verified in polynomial time is known as NP. Equivalently, NP is the class of decision problems that can be solved in polynomial time on a non-deterministic Turing machine (NP stands for Nondeterministic Polynomial time).
Computational complexity theory
A single "problem" is an entire set of related questions, where each question is a finite-length string. For example, the problem FACTORIZE is: given an integer written in binary, return all of the prime factors of that number. A particular question is called an instance. For example, "give the factors of the number 15" is one instance of the FACTORIZE problem.
The time complexity of a problem is the number of steps that it takes to solve an instance of the problem as a function of the size of the input (usually measured in bits), using the most efficient algorithm. To understand this intuitively, consider the example of an instance that is n bits long that can be solved in n² steps. In this example we say the problem has a time complexity of n². Of course, the exact number of steps will depend on exactly what machine or language is being used. To avoid that problem, we generally use Big O notation. If a problem has time complexity O(n²) on one typical computer, then it will also have complexity O(n²p(n)) on most other computers for some polynomial p(n), so this notation allows us to generalize away from the details of a particular computer.
Example: Mowing grass has linear complexity because it takes double the time to mow double the area. However, looking up something in a dictionary has only logarithmic complexity because a double sized dictionary only has to be opened one time more (e.g. exactly in the middle - then the problem is reduced to the half).
Problems that are solvable in theory, but cannot be solved in practice, are called intractable. What can be solved "in practice" is open to debate, but in general only problems that have polynomial-time solutions are solvable for more than the smallest inputs. Problems that are known to be intractable include those that are EXPTIME-complete. If NP is not the same as P, then the NP-complete problems are also intractable.
To see why exponential-time solutions are not usable in practice, consider a problem that requires 2n operations to solve (n is the size of the input). For a relatively small input size of n=100, and assuming a computer that can perform 1010 (10 giga) operations per second, a solution would take about 4*1012 years, much longer than the current age of the universe.
An example of an NP-hard problem is the decision problem SUBSET-SUM which is this: given a set of integers, does any non empty subset of them add up to zero? That is a yes/no question, and happens to be NP-complete.
There are also decision problems that are NP-hard but not NP-complete, for example the halting problem. This is the problem "given a program and its input, will it run forever?" That's a yes/no question, so this is a decision problem. It is easy to prove that the halting problem is NP-hard but not NP-complete. For example the Boolean satisfiability problem can be reduced to the halting problem by transforming it to the description of a Turing machine that tries all truth value assignments and when it finds one that satisfies the formula it halts and otherwise it goes into an infinite loop. It is also easy to see that the halting problem is not in NP since all problems in NP are decidable and the halting problem is not.
The complexity class EXPTIME-complete is also a set of decision problems. A decision problem is in EXPTIME-complete if it is in EXPTIME, and every problem in EXPTIME has a polynomial-time many-one reduction to it. In other words, there is a polynomial-time algorithm that transforms instances of one to instances of the other with the same answer. EXPTIME-complete might be thought of as the hardest problems in EXPTIME. Notice that although we don't know if NP-complete is a subset of P or not, we do know that EXPTIME-complete lies outside P; none of these problems can possibly be solved in polynomial time.
In computability theory, one of the basic undecidable problems is that of deciding whether a deterministic Turing machine (DTM) accepts a particular input. One of the most fundamental EXPTIME-complete problems is a simpler version of this which asks if a DTM accepts an input in at most k steps. It is in EXPTIME because a trivial simulation requires O(k) time, and the input k is encoded using O(log k) bits.4 It is EXPTIME-complete because, roughly speaking, we can use it to determine if a machine solving an EXPTIME problem accepts in an exponential number of steps; it will not use more.
Other examples of EXPTIME-complete problems include the problem of looking at a generalized Chess, Checkers, or Go position, and determining whether the first player can force a win. These games are EXPTIME-complete because games can last for a number of moves that is exponential in the size of the board. By contrast, generalized games that can last for a number of moves that is polynomial in the size of the board are often PSPACE-complete.
Notice that the NP-complete problem resembles a typical puzzle: is there some way to plug in values that solves the problem? The PSPACE-complete problem resembles a game: is there some move I can make, such that for all moves my opponent might make, there will then be some move I can make to win? The question alternates existential and universal quantifiers. Not surprisingly, many puzzles turn out to be NP-complete, and many games turn out to be PSPACE-complete.
Examples of games that are PSPACE-complete (when generalized so that they can be played on an n × n board) are the games hex and Reversi and the solitaire games Rush Hour, mahjong, Atomix and Sokoban. Some other generalized games, such as chess, checkers (draughts), and go are EXPTIME-complete because a game between two perfect players can be very long, so they are unlikely to be in PSPACE.
Note that the definition of PSPACE-complete is based on asymptotic complexity: the time it takes to solve a problem of size n, in the limit as n grows without bound. That means a game like checkers (which is played on an 8 × 8 board) could never be PSPACE-complete (in fact, they can be solved in constant time and space using a very large lookup table). That is why all the games were modified by playing them on an n × n board instead; in some cases, such as for Chess, these extensions are somewhat artificial and subjective.
Posted by Jon Rubin at 10:57 PM | Comments (0) | TrackBack