April 2, 2009
In which the heart muscle mass continues to grow
In a finding that may open new approaches to treating heart disease, Swedish scientists have succeeded in measuring a highly controversial property of the human heart — the rate at which its muscle cells are renewed during a person’s lifetime. The finding upturns what has long been conventional wisdom: that the heart cannot produce new muscle cells and so people die with the same heart they were born with. About 1 percent of the heart muscle cells are replaced every year at age 25, falling to less than a half of a percent per year at age 75, concludes a team of researchers led by Dr. Jonas Frisen of the Karolinska Institute in Stockholm.... Read more
December 10, 2008
יש דבר שיאמר ראה זה חדש הוא כבר היה לעלמים אשר היה מלפננו׃
Codex Sinaiticus. Although the screen controls tend towards inaccurate, seeing the codex itself in such clear reproduction is a joy. The lettering is beautiful and clear, and the accompanying modern text rendering useful for navigation. Now if only I could find a reasonable online edition of the Hebrew text .... Aha: looking through Google for the Hebrew phrase turned up a few sites with multi-lingual texts (and some imaginative renderings) of Ecclesiastes. יֵשׁ דָּבָר שֶׁיֹּאמַר רְאֵה-זֶה, חָדָשׁ הוּא: כְּבָר הָיָה לְעֹלָמִים, אֲשֶׁר הָיָה מִלְּפָנֵנוּ.... Read more
Of courtesans and fish-cakes
[The Max Planck Institute] wanted Chinese classical texts to adorn its journal, something beautiful and elegant, to illustrate a special report on China. Instead, it got a racy flyer extolling the lusty details of stripping housewives in a brothel. Chinese characters look dramatic and beautiful, and have a powerful visual impact, but make sure you get the meaning of the characters straight before jumping right in. ... The use of traditional Chinese characters and references to "the northern mainland" seem to indicate the text comes from Hong Kong or Macau, and it promises burlesque acts by pretty-as-jade housewives with hot bodies for the daytime visitor. To be sure, the Romans of yore had courtesans; I expect classical Chinese society ditto.... Read more
December 5, 2008
The revolution will be televised
Different revolution, different cube, still fascinating. Also: JP Brown's Serious LEGO, All Too Flat's Astor Place Rubik's Cube.... Read more
November 5, 2008
In defense of levers
Richard Hayes has a good piece on the reliability and accuracy of mechanical voting machines. Compare to the Village Voice's running discussion on the coming generation of super voting machines.... Read more
October 27, 2008
September 27, 2008
June 12, 2008
Ys
While looking up the mythical town in France, Wikipedia's helpful disambiguation page pointed me in the direction of the yoctosecond, a unit of time representing one-quadrillionth of a second. Yocto is the smallest of the SI units, denoting a factor of 10−24. The yotta in yottasecond, with the same ys abbreviation, denotes a factor of 1024 and is the largest SI unit.... Read more
June 7, 2008
In which we face the end of guano
“It would be an inglorious conclusion to something that has survived wars and man’s other follies,” Mr. de la Torre said. “But that is the scenario we are facing: the end of guano.” An article in The New York Times discusses the precarious position of the guano-collecting industry off the Peruvian coast. I learned of guano from the Tintin adventure Prisoners of the Sun.... Read more
June 6, 2008
How many Luxemborgs is Wales?
Arf's Sensible Units web site elegantly converts one measurement — 181 cm, say, — into something less abstract: 1.3 Alaskan moose antler spans. 15 CDs side by side. A little less scientific (and more joyful: "Convert boring units to real objects as you type!" is its slogan) than the sensational Google Calculator, but no less useful. For the record: 1 Wales is 8.0 Luxemborgs.... Read more
May 30, 2008
The view along 28.9º offset
This should have been a perspective of the setting sun, the disc revealed in its entirety, but clouds moved in late afternoon and spoiled an otherwise spectacularly sunny day. The phenomenon of Manhattanhenge occurs a few times each other, but none as spectacularly as in late May. The term comes from an article in Natural History magazine by the astronomer Neil DeGrasse Tyson.... Read more
May 6, 2008
In which we warm to the new theories
The New York Times ran an excellent and exciting story about research at Lake Baikal. The story excited me for many reasons: a family has, from one generation to the next, steadily collected data about the water and the ecology of the lake. Every week to 10 days, by boat in summer and over the ice in winter, he crossed the lake to a spot about a mile and a half from Bolshie Koty, a small village in the piney woods on Baikal’s northwest shore. There, Dr. Kozhov, a professor at Irkutsk State University, would record water temperature and clarity and track the plant and animal plankton species as deep as 2,400 feet. Soon his daughter Olga M. Kozhova began assisting him and, eventually her daughter, Lyubov Izmesteva, joined the project. They kept at it over the years, producing an extraordinary record of the lake and its health. Now Dr. Izmesteva and scientists in the United States have analyzed the data and concluded, to their surprise, that the water in Lake Baikal is rapidly warming. As a result, its highly unusual food web is reorganizing, as warmer water species of plankton become more prevalent. These shifts at the bottom of the food web could have important implications for all of the creatures that live in the lake, they say. Although Dr. Kozhov is famous among scientists who study lakes — his 1961 book “Lake Baikal and Its Life” is considered a classic — the new report is “the international debut of the Kozhov family’s legacy of research,” Stephanie E. Hampton of the National Center for Ecological Analysis and Synthesis at the University of California, Santa Barbara, said in an e-mail message. Props to the New York Times for implementing a "Share" feature that provides an easy-to-use "permalink" to each of its articles. This is the paper of record, yearning to be free.... Read more
February 8, 2008
In which we rock out to math
Math and music, but not math rock: "Guthrie's daughter Nora eventually figured out that the [mess of wires] wasn't a bomb, but rather a recording of her father on a device that predated magnetic tape. After a year of searching, she managed to track down someone with the equipment to play it." "Fortunately, math can help. Howarth had developed algorithms to correct these recordings. He looks for extraneous sounds, like an air conditioner or fan in the background that creates a rhythmic sound. Instead of simply removing these sounds, he uses them as a clock, a kind of built-in foot-beat in the recording that tells him what the true timing should be. When a recording is made, this background rhythm is even. But when it's played back, it speeds up and slows down in perfect timing with the errors in the recording. That allows Howarth to adjust the timing of the recording to make it much more similar to the original sound."... Read more
February 3, 2008
In which we have science without tears
New Zealand: ‘No Tears’ Onions By AGENCE FRANCE-PRESSE Published: February 2, 2008 A New Zealand concern called Crop and Food Research said on its Web site that it had created a tearless onion by turning off the gene that produces the enzyme that causes a person slicing an onion to cry. It hopes it can hit the market within a decade. The breakthrough was featured in the December issue of Onion World, the international onion trade journal. A picture (well, screenshot) might help:... Read more
February 2, 2008
Over the Edge of the World
Voyagers in the Age of Discovery trained in formal schools, where they learned the science of navigation, theories of cartography, and the immense trove of history essential to understanding of exploration. In Castilian Spain,the Casa de Contratraci�n's "School of Navigation [provided] formal training [to] pilot[s], probably from the boastful and controversial Amerigo Vespucci .... Students received credit in the form of beans won from their instructor; if they successfully completed a course, they were awarded a dry bean; if unsuccessful, they received a shriveled pea." Casa de Contratraci�n was the "House of Commerce", and provided the financial backing for the highly-speculative and incredibly dangerous voyages to the Spice Islands. Contrast this to the school in William Langweische's Outlaw Sea, which involved real-world simualations in the South of France, complete with scale-model ships of all varieties. Laurence Bergreen's story of Magellan focuses on his monumental 'round-the-world voyage. Leaving much of Magellan's early story behind, he paints a portrait of a barely competent navigator whose luck and hardheadedness combined to take him most of the way around the globe. Although Ferdinand Magellan's expedition and its findings (yes! the world is round!) are tremendous, they now seem to me more the result of chance than of calculation. Magellan did not have an aptitude for scholarship, and was no master of instruments; his cosmologist collaborator went insane before the ships sailed. He faced many political obstacles, both in the Portuguese empire and in the Spanish court of Charles I, and showed little aptitude for handling the intrigue. . The book itself starts slowly, but once the voyage is underway the excitement begins: cannibals! giants! williwaws! mutiny! exotic islands! spices! update I plumb forgot one of the other exciting passages of this book: Bergreen recounts the punishments that the hapless Magellan metes out in revenge for the first mutiny, and describes a form of torture especially beloved by the Spanish Inquisition. Torquemada was as fond of waterboarding as are the United States Attorneys General. Even as he engaged in the clear acts of torture, Magellan knew that he would receive dishonor upon his return to Spain. Five hundred years later: Plus ça change, plus c'est la même chose.... Read more
January 29, 2008
In which we go into the fold
Robert Lang writes on origami art and science. He makes mathematical, handsome arthropods from paper.... Read more
January 28, 2008
A Briefer History of Time
Stephen Hawking presents an illustrated, clarified version of his A Brief History of Time. This edition presents the enthralling concepts of particle physics, general relativity, quantum mechanics, and other concepts understood by fewer than a dozen people throughout the space-time continuum. I do love a book in which the author describes physical laws through narration, rather than through explicit derivation of equations. (One exception to this is David Flannery's excellent examination of the square root of two.) Hawking's presentation falls back a little too easily on a Creator, and does not strongly suggest that physics can indeed solve all problems — as I know it does. Hawking describes moments in which he falls back to the notion of non-physical intervention, specifically at the outset of the creation of this universe. After all, how does one explain the presence of energy that became the matter of our universe? What is the answer to "What came before the Big Bang?" The illustrations in this edition struck me as kitsch, which at some level is appropriate for a discussion of cosmology, but ultimately distracted me from the useful passages in the text itself.... Read more
January 11, 2008
In which we consider a museum
Briefly: I heard Robin Nagle of NYU talk about the history of the New York City Department of Sanitation. More soon.... Read more
December 27, 2007
In which unique is where you find it.
In a volume of Isaac Asimov's collected stories, "The Edge of Tomorrow", one of the most enjoyable stories is "Unique is Where You Find It", about a neurotic graduate student and his obstinate advisor, and their discussion of the naming of elements. I came across a reference to an element called "ekamanganese"; this aroused my curiosity, as the parts of the name looked familiar, yet I was certain that no element exists with this same name. A look across the Internet produced a citation to a note that presents reasons why Mendeleev chose now-superseded Sanskrit names for eight elements in the periodic table. The Russian scholar Dmitri Mendeleev created the periodic table of the elements, a masterpiece of instructional design and a wonder in its many aspects, and also predicted the composition of many elements not yet discovered in his day. The syllable eka comes from the Sanskrit word meaning "one"; it appears as an element in many Sanskrit words. No pun intended. Time Magazine noted in 1930 that "Eka, Sanskrit for one or first, is a prefix applied to the first undiscovered element in a group of the periodic system." The connections between classical Sanskrit poetry and Mendeleev's periodic table strike me as sublime. The author of the note above reaches the conclusion that "... Mendeleev, by using Sanskrit names, was tipping his hat to the Sanskrit grammarians of yore, who had created astonishingly sophisticated theories of language based on their discovery of the two-dimensional patterns in basic sounds." One of the more interesting passages in the note come from "private communication" between the author and the linguist (ha, there's another fine Sanskrit word for you) Paul Kiparsky: who found "striking similarities between the Periodic Table and the introductory Śiva Sūtras in [5th-century grammarian] Panini’s grammar ...". The Asimov story uses the faithful mechanism of "The butler did it" (sort of) to wrap up its narrative, but the exposition contains a succinct discussion, courtesy of Asimov's Black Widowers Club, of almost all the elements and the composition of their names.... Read more
December 20, 2007
In which we stop to admire a Taxicab
Once, in the taxi from London [to Putney], Hardy noticed its number, 1729. He must have thought about it a little because he entered the room where Ramanujan lay in bed and, with scarcely a hello, blurted out his disappointment with it. It was, he declared, "rather a dull number," adding that he hoped that wasn't a bad omen. "No, Hardy," said Ramanujan. "It is a very interesting number. It is the smallest number expressible as the sum of two [positive] cubes in two different ways." The Taxicab problem is well-documented, including two entries in the On-Line Encyclopedia of Integer Sequences: A011541 and A047696. To many mathematicians, the mere mention of the number 1729 recalls the incident involving mathematicians G.H. Hardy and Srinivasa Ramanujan; thus, to commemorate the Hardy-Ramunujan conversation, the least number which is the sum of two positive cubes in n different ways is called the nth taxicab number: For any n >= 1, there indeed exist numbers which are the sum of two positive cubes in n ways, which guarantees the existence of Taxicab(n) for n >= 1. A corollary: Cabtaxi(n) the smallest positive integer which can be written as the sum of two positive or negative cubes in n ways.... Read more
December 18, 2007
Distributed Systems: Principles and Paradigms
Reading an author as energetic as Andrew Tanenbaum explain concepts of distributed processing, network topology, and resource allocation is all sorts of awesome. This second edition of the work, by Vrije Universiteit Amsterdam colleagues Tanenbaum and Marten van Steen brings together the essential concepts of distributed computing. I kept forgetting that it is a text, written for use in the classroom, until I reached the end of each chapter and found the exercise questions ( some answers available online) -- it is as thrilling to read as any mystery book.... Read more
November 28, 2007
In which we drink from a Kleinsche Flasche
For many years I was not an adherent of the television program "Futurama", although it fit my "A"-list criteria: animated, amusing. Now that I know how many nurdalicious maths jokes the show has, I am eager to watch it. A Klein bottle has neither inside nor outside; it is a closed, nonorientable surface of Euler characteristic. Legendary sysadmin Cliff Stoll makes these "One sided, boundless, and mathematically nonorientable" bottles for sale, as well as steins after the same fashion; one could indeed drink from a Kleinsche Flasche!... Read more
October 20, 2007
In which we excavate, virtually
As an update to http://salim.virji.net/blog/2007/09/13/broadway_and_bowling_green" title="Broadway and Bowling Green">the online map of Broadway and Bowling Green, I offer this historical map of Lower Manhattan, and this virtual tour.... Read more
October 15, 2007
Bees3
Bees, bees and elephants, invisible bees. To get a honeybee hive ready to pollinate almonds in February, beekeepers must trick the bees into thinking it's spring, so the hive will be forced to lay brood, build its numbers and fatten its workers. Pollen patties - caked mixtures of sucrose, brewer's yeast and human-harvested flower pollen often imported from China are fed to the bees. Corn syrup is pumped into a plastic feeder in each hive through a gas pump. The mixture is tough to get right, and often gives the bees nosema, or diarrhea. Beekeepers spend an average of $20 per hive on winter feed. For a modest operation with 2,500 hives, that's a $50,000 bill for fake flowers. Those who migrate to California in the fall to prep their bees for the almonds must find land to put them on. As development sucks up open space, many beekeepers find themselves driving farther and farther to their bee yards. Recently, some beekeepers are experimenting with storing hives for the winter in temperature-controlled potato cellars in the High Plains, and trucking them in right before bloom, saving on feeding costs. The Chronicle article quoted above also has tit-bits on the second-largest beekeeper in the States (now that's an image) and on the honeybee matchmaker, whose wife's name is a palindrome for amen. All together, the narrative of the agribusiness of honey and almonds, two beautiful foods, makes me a little queasy. The characters might have stepped from a David Lynch movie, the farmers become further entrenched in abysmal business and poor agriculture, and China makes all the money.... Read more
September 28, 2007
In which the borough welcomes a baby
My favourite walrus, Ayveq of the New York Aquarium, welcomed his new baby boy, one of a mere handful born in captivity . Lots of photos online.... Read more
September 22, 2007
In which we colon wonder
Why bother studying robotics? So that you can get arrested by the hair-trigger patrols at Logan? Arrested, or almost shot? Star Simpson, the MIT student in question, wore a home-made art-robotics project to Logan and wound up in pokey. All three of the above news stories are essentially the same: there's no new news. In case you forgot, Boston over-reacted earlier this year, too.... Read more
September 9, 2007
The Mystery of the Disappearing Inland Sea
The modern story of the Aral Sea is not a mystery: The Art of Mapping on the Run is the New York Times' perspective: 'In the new edition of “The Times Comprehensive Atlas of the World” (Times Books, London, 2007), for instance, there are before-and-after views of the Aral Sea, once the world’s fourth-largest lake. It shriveled as Soviet-era irrigation projects siphoned off the rivers that replenished it. A dam completed in 2005 now prevents water from flowing out of the lake’s northern lobe, which is expanding as a result.' The BBC perspective is less philosophical, and bluntly explains that the folly of human industry caused the changes to the sea. Somewhere in a box we have a massive copy of the Times Atlas, probably from '04, and I wonder how the Aral looks in that one.... Read more
September 6, 2007
In which the evidence presents itself
An article in the San Francisco Chronicle reports: On Thursday, in the journal Nature, a group headed by William F. Bottke, an asteroid expert at the Southwest Research Institute in Boulder, Colo., traces that impact back to a giant asteroid named Baptistina nearly 100 miles in diameter. Baptistina, the team of scientists say, was rammed by another, unnamed asteroid at least 35 miles in diameter in a violent collision about 160 million years ago - give or take 20 million years. The collision showered nearby space with at least 300 fragments bigger than 20 miles in diameter and more than 140,000 smaller asteroids, each one more than 3 miles around, Bottke contends. The smaller asteroids are now known as the Baptistina family, and according to Bottke and his colleagues - David Vokrouhlicky of Chares University in Prague and David Nesvorny of Bottke's institute - it was one of those "refugees" from Baptistina that created the 110-mile-wide Chicxulub crater. Not only that, they say, it was another earlier Baptistina offshoot asteroid that crashed into the moon about 110 million years ago and gouged out the well-known lunar crater called Tycho, whose debris the Apollo 17 astronauts encountered on America's last manned flight to the moon 35 years ago. The usual childhood fascination with dinosaurs took hold of me specifically in two ways: we lived quite near a natural-history museum with a massive dinosaur hall, and school trips frequently took us there to gape in awe at the forty-foot high (or long) skeletons; and in junior-high, my father and I heard the Doctors Alvarez, pere et fils, speak in a small lecture hall on the campus of the University of Pittsburgh. The notion that we could track an event so long ago through a combination of archaeology, palaeontology, astrophysics, and intuition staggered me.... Read more
August 30, 2007
In which we go exploring
Illicit Ohio and The Vanishing Point explore abandoned or unexplored pieces of our massive urban infrastructure, in Cincinnati and Toronto respectively.. Many of the sites result from intrepid explorers lifting up manholes, sliding down drains, and inveigling themselves into unusual physical situations; the resulting photographs are dramatic and useful. A pragmatic example of why understanding this infrastructure proves useful comes via Pittsburgh: Pittsburgh's water mains have a seven-year itch or something, as the same water main has ruptured twice now. Plenty of exploration and publication about urban infrastructure concerns New York: photographer Stanley Greenberg published a volume, entitled Invisible New York, with beautiful images of substations, utility passages, and tunnels from around the city. From photographic evidence to anecdotal accounts, we arrive at people living in old rail tunnels; I discount these stories of "Mole People" as a sort of folklore, due to lack of substantiation: they seem more a romantic idea, or wishful thinking, that communities of social outcasts live on the physical and cultural fringe of New York City, underneath is massive parks and in its abandoned subway tunnels.... Read more
August 26, 2007
In which we fight fires
The New York Times has a nice piece explaining the purpose of the Siamese outside many buildings in Manhattan: the standpipe system. "At many buildings, parts of the Siamese and the plates covering the opening where it goes through the facade are brass, and it appears to be a point of pride among building managers or maintenance workers to keep that brass polished to a high shine." More photographs of and the law concerning standpipes.... Read more
August 13, 2007
In which we are ignoring the supercomputer in the room
My father sent along two articles on the Chudnovsky Mathematician from The New Yorker magazine: on the reconstruction of the Unicorn Tapestry at The Cloisters; and on the search for π with a home-made supercomputer. Richard Preston's articles are fun, lucid, and breath-taking: the sheer inventiveness of the science that the Mathematician (for they are an entity comprised of two individual bodies) tackles, and the delirious interaction with the physical world — a computer built of parts from Home Depot, tucked into a two-bedroom apartment — a discovery of the warp and weft of one of the world's most intricate tapestries — make the articles all the more delightful.... Read more
August 10, 2007
In which we take this world by storm and we don't look back
This totally burly video is Nature in Action. This video is the reason that YouTube rocks. This video is absolutely enthralling. You know: "lions always hit the heights / 'cause to kill it's always been an easy way out"... Read more
August 7, 2007
In which I'm on fire
As scientists identified the region of the brain responsible for fever, I had a rapidly-increasing reading on the thermometer. “But in fact,” [Dr Clifford Saper] said, “they are part of an adaptive response, coordinated by the hypothalamus, to help you survive an infection. “If you raise the body’s temperature a few degrees, white blood cells become more active; they actually fight harder. But most bacteria don’t grow as well.” For that reason, he said, fever can help the body quash bacterial infection. Similarly, loss of appetite may help deprive bacteria of needed glucose. The aches and pains may make a sick person lie down and conserve energy.... Read more
July 19, 2007
In which we understand the recursion
Two professors at University College London have published their solution to describing a perplexing shape in three dimensions. The Möbius Strip has long fascinated me, from the literature about it to the topological conundrum it presents. The strip is made from what mathematicians call a 'developable' surface, which means it can be flattened without deforming its shape — unlike, say, a sphere. When a developable surface is formed into a Möbius strip, it tries to return to a state of minimum stored elastic energy, like an elastic band springing back after being stretched. But no one has been able to model what this final form will be. "The first papers looking at this problem were published in 1930," says Starostin. "It seems such a simple question — children can make these things — but ask the experts how to model this shape and we've had nothing."... Read more
July 7, 2007
In which we have built a competitive system
Tushar Chandra, Robert Griesemer, and Joshua Redstone published a paper on a commercial implementation of Leslie Lamport's Paxos [a href="http://research.microsoft.com/users/lamport/pubs/paxos-simple.pdf" title="Offsite: Paxos Made Simple (PDF)">PDF] consensus algorithm; they describe their efforts at building and deploying their system in Paxos Made Live. (The paper appeared in PODC '07: 26th ACM Symposium on Principles of Distributed Computing, and is published at the link above through Google.) Synchronization, consensus, and contention-resolution are fundamental and beautiful problems in a distributed system, and I enjoyed reading this paper (Disclaimer: I was a peer reviewer for the paper in draft).... Read more
March 29, 2007
On the geometry of (outer) space
Hexagons in space, such as these captured by the Cassini mission to Saturn, may come from vortices of liquid swirling under pressure; the resulting instability produces a regular polygon.... Read more
March 20, 2007
In which Nature treats us
I know donuts, and this is snow donut. Dough snownuts? Government-documented, even. It's the same principle as making a snowman, except it's nature doing the rolling. And it doesn't happen often, says Paul Pastelok, an AccuWeather meteorologist in State College, Pa. "The snow has to be fresh and moist enough to be cohesive but not as moist as the snow we had Monday. There has to be a wind strong enough to get the snow rolling (40 mph sustained ...), but not so strong it blows it away. And there has to be a slope, at least initially, for momentum." -- from the Cincinnati Enquirer.... Read more
February 23, 2007
In which we flip it for real
A circumzenithal arc, you say? Here is another, wraithlike photograph.... Read more
January 12, 2007
In which we get the real first roll at tavula
A backgammon blast from the past: The oldest backgammon in the world along with 60 pieces has been unearthed beneath the rubbles of the legendary Burnt City in Sistan-Baluchistan province, southeastern Iran. Iranian archeologists working on the relics of the 5,000-year-old civilization argue this backgammon is much older than the one already discovered in Mesopotamia and their evidence is strong enough to claim the board game was first played in the Burnt City and then transferred to other civilizations. "The backgammon reveals intriguing clues to the lifestyle of those people," said Mansour Sajjadi, head of the research team. "The board is rectangular and made of ebony, which did not grow in Sistan and merchants used to import it from India." He added the board features an engraved serpent coiling around itself for 20 times, thus producing 20 slots for the game, more affectionately known in Persian as Nard. The engraving, artistically done, indicates artisans in the Burnt City were masters of the craft. "The 60 pieces were also unearthed inside a terracotta vessel beside the board. They were made of common stones quarried in the city, including agate and turquoise," Sajjadi added. Experts still wonder why they played the game with 60 pieces and are trying to discern its rules, but it at least shows it is 100-200 years older than the one discovered in Mesopotamia. They are also intrigued that inhabitants of ancient civilizations, widely believed to be concerned with their daily survival, could afford to indulge in such luxuries as playing board games.... Read more
December 25, 2006
In which the honey is in the vac
The Los Angeles Times has a series on the Oceans, and the latest instalment describes a new water-treatment facility in Santa Monica, SMURFF.... Read more
December 20, 2006
In which moths drink your tears while you sleep
An article in New Scientist describes howcertain moths have adapated to drinking the tears from sleeping birds. This is the sort of story one expects Rosamund Purcell to photograph.... Read more
November 27, 2006
In which Gibraltar is still firmly attached
One of the casualties of being unceremoniously dunked in a tepid lake was my wallet, which began rusting — the lake was fed by sea-water, apparently, and was unusually saline. The wallet has accompanied me for about fifteen years, since I bought it on an expedition to The Alley (Clark St location, mind you) (and, quite probably, Mama Desta's. Yum). I salvaged most of the contents, bought new stamps, but alas!, a Financial Times clipping is almost ruined. For posterity, I include it here, although without the slight pink tint characteristic of that journal. From the Marques de Lendinez. Sir, The informative item in your People column (December 20) about Sir Francis Richards, the next governor of Gibraltar, was marred by the repeated references to Gibraltar being an island. Last week, when I was on the Rock, Gibraltar was firmly attached to the Iberian Peninsula. [The address, in boldface type, is now illegible and ragged] The original clipping came to my wallet by way of Mr Aram Shumavon, a careful reader indeed.... Read more
November 1, 2006
Some thoughts on trash
Some comments in aFrieze column about trash reminded me that I am very curious about how civilization measures itself on trash collection. I take photographs of recycling schemes, and of street cleaners, and I wonder about whether our advanced in trash separation mean that our society is progressing.... Read more
August 14, 2006
In which we wonder: is it animal? or vegetable? or mineral?
Willi Hennig was an entolmologist who developed a theory of phylogenetic systematics, describing how species relate to each other, which has led to the study known as cladistics. This story about a deep-sea-dwelling blind antarctic sea spider underscores the difficulty of classification.... Read more
August 8, 2006
kapok
kapok is a tall tropical West African tree; the fibre obtained from its seed pods can stuff zafus and other cushions. It is also the national tree of Puerto Rico.... Read more
July 11, 2006
In which there be serpents
The SERPENT project, Scientific and Environmental ROV Partnership using Existing iNdustrial Technology, has some intriguing photographs from a recent deep-sea photography competition.... Read more
July 10, 2006
In which we burn a cartoon flag
Amongst the usual self-indulgent signatures ("Sent from my Blackberry wireless handheld", the latest college football scores, the redundant email address) in colleagues' email messages, I found this gem: The study by the new McCormick Tribune Freedom Museum found that 22 percent of Americans could name all five Simpson family members, compared with just one in 1,000 people who could name all five First Amendment freedoms. The study by the McCormick Tribune Freedom Museum exists for the promotion of "religious, scientific, literary or educational purposes or for the prevention of cruelty to children or animals." The First Amendment provides us with the liberty to satire, so gleefully used in The Simpsons -- in one episode, Homer literally hides behind the Constitution.... Read more
July 6, 2006
In which we set TIMEZONE
The standardization of time is of critical importance to electronics engineering, and especially to computing. The United States Mobile Aeronautics Education Laboratory has a brief quiz on time, and the Free BSD Diary has a succint piece on time zones in FreeBSD. I have relied on Kerberos for authentication, and Kerberos can be subverted by time skew. Unhelpfully, the origin of "jiffy" remains unknown, leaving the etymology of an exciting and euphonic word a mystery.... Read more
June 28, 2006
In which we get serious about metric
Aram, with the keen eye of a researcher, pointed out the latest developments in metric measurements.... Read more
June 9, 2006
In which we discover the prettiest star
I free-associated while reading about a particular sort of star (informally known as "splat" or "asterisk", I guess), and thought about different kinds of non-celestial stars. The candidates: Wandering Star, the haunting post-modern torch song by Portishead. The Prettiest Star, the lush single David Bowie released in 1970 at the apex of the glam racket. Kleene Star, which is an operation on a set of strings that produces the set of component strings, including the empty string. The motto "Kleeneliness is next to Gödeliness" made me chuckle. I discovered Planet Math while looking for information about the Kleene Star, and find the wiki-based collaborative maths encyclopædia quite compelling.... Read more
June 8, 2006
On water and corn
A bottle of Biota Spring Water advertises that the bottle is biodegradeable. In fact, the bottle is "made from a 100% renewable resource, corn". Although corn is renewable, that fact does not endorse our approach: that we should renew corn corps in the way that we do. Since the 70s the United States has contributed to a national surplus of corn without increasing the world's ability to feed its population, and has increased the corn supply specifically for the benefit of few. Many of the corn products we see and consume in our everyday chores are a direct result of the gross corn surplus: the necessity to consume the surplus became the mother of invention. In this case, the invention is the bottle: NatureWork ™PLA uses 30% to 50% less fossil fuel to produce than petroleum-based plastics. Although it decomposes naturally, the bottle still requires energy to produce, and from a source that we renew at great expense to the American taxpayer: $5 to $20 billions annually. Other by-products of the corn surplus include high-fructose corn syrup (HFCS, chemically guided to taste exactly like naturally-occurring sugars); corn-fed beef, and accordingly lower beef prices (and quality); and, perhaps most damning of all, monocultural agribusiness which encourages the industrialization of all aspects of the food chain, at the expense of agricultural diversity and of environmental stewardship.... Read more
June 5, 2006
Of warm beer and cold coffee
I find that I prefer warm beer and cold coffee. Warm beer: typically British ale, drawn from a hand-pump. The beermapping project presents a nice view of the city, although really what matters is Magnolia. Cold coffee: not coffee poured over ice, but coffee brewed through a cold-water process. I discovered this at Barefoot Coffee Roasters, where the engaging baristas make all sorts of whimsical drinks (several recent concoctions have involved a culinary torch!).... Read more
May 24, 2006
In which we study the design of trains
A Parable by Edsger W.Dijkstra, sometime in 1973. Years ago a railway company was erected and one of its directors -- probably the commercial bloke -- discovered that the initial investments could be reduced significantly if only fifty percent of the cars would be equipped with a toilet, and, therefore, so was decided. Shortly after the company had started its operations, however, complaints about the toilets came pouring in. An investigation was carried out and revealed that the obvious thing had happened: despite its youth the company was already suffering from internal communication problems, for the director's decision on the toilets had not been transmitted to the shunting yard, where all cars were treated as equivalent, and, as a result, sometimes trains were composed with hardly any toilets at all. In order to solve the problem, a bit of information was associated with each car, telling whether it was a car with or without a toilet, and the shunting yard was instructed to compose trains with the numbers of cars of both types as equal as possible. It was a complication for the shunting yard, but, once it had been solved, the people responsible for the shunting procedures were quite proud that they could manage it. When the new shunting procedures had been made effective, however, complaints about the toilets continued. A new investigation was carried out and then it transpired that, although in each train about half the cars had indeed toilets, sometimes trains were composed with nearly all toilets in one half of the train. In order to remedy the situation, new instructions were issued, prescribing that cars with and cars without toilets should alternate. This was a move severe complication for the shunting people, but after some initial grumbling, eventually they managed. Complaints, however, continued and the reason turned out to be that, as the cars with toilets had their toilet at one of their ends, the distance between two successive toilets in the train could still be nearly three car lengths, and for mothers with children in urgent need -- and perhaps even luggage piled up in the corridors -- this still could lead to disasters. As a result, the cars with toilets got another bit of information attached to them, making them into directed objects, and the new instructions were, that in each train the cars with toilets should have the same orientation. This time, the new instructions for the shunting yard were received with less than enthusiasm, for the number of turntables was hardly sufficient; to be quite fair to the shunting people we must even admit that according to all reasonable standards, the number of turntables was insufficient, and it was only by virtue of the most cunning ingenuity, that they could just manage. With all toilets equally spaced along the train the company felt confident that now everything was alright, but passengers continued to complain: although no passenger was more than a car length away from the nearest toilet, passengers (in urgent need) did not know in which direction to start their stumbling itinerary along the corridor! To solve this problem, arrows saying "TOILET" were fixed in all corridors, thereby also making the other half of the cars into directed objects that should be properly oriented by the shunting procedure. When the new instruction reached the shunting yard, they created an atmosphere ranging from despair to revolt: it just couldn't be done! At that critical moment a man whose name has been forgotten and shall never be traced, made the following observation. When each car with a toilet was coupled, from now until eternity, at its toileted end with a car without a toilet, from then onwards the shunting yard, instead of dealing with N directed cars of two types, could deal with N/2 identical units that, to all intents and purposes, could be regarded as symmetrical. And this observation solved all shunting problems at the modest price of, firstly sticking to trains with an even number of cars only -- the few additional cars needed for that could be paid out of the initial savings effected by the commercial bloke! -- and, secondly, slightly cheating with regard to the equal spacing of the toilets. But, after all, who cares about the last three feet? Although at the time that this story took place, mankind was not blessed yet with automatic computers, our anonymous man who found this solution deserves to be called the world's first competent programmer. I have told the above story to different audiences. Programmers, as a rule, are delighted by it, and managers, invariably, get more and more annoyed as the story progresses; true mathematicians, however, fail to see the point. Dijkstra developed the concept of semaphores for inter-process communication. He also described the problem of deadlocks, as eventually retold in the Dining Philosophers Problem.... Read more
May 4, 2006
In which we encounter a Byzantine problem
Leslie Lamport, on the pluscal page, provides a 21-character string on which to search for the page. The string, which he requests others refer to as "the string obtained by removing the - from uid-lamportpluscalhomepage". The use of a string like this to identify the page strikes me a strange, betraying a lack of trust in the algorithms that allow quick and efficient search of the internet, and especially strange considering that Lamport is an expert on algorithms and systems. He presents the scenario of distributed decision-making in The Byzantine Generals Problem. The issue of fault tolerance in large, necessarily distributed, and often diverse systems presents fabulously difficult challenges. Lamport's private search string turns out to be a googlewhack, which "existential manatee" is not.... Read more
April 24, 2006
In which we have a thousand sanguinary guillotines
The enigmatic Françpois-René de Chateaubriand gives his name to a most delicious preparation of tenderloin. A very different recipe from the traditional "Pittsburgh" rare steak of my youth. Portraits of this playboy noble show him looking rakish and dissolute -- quite probably from eating his chef's fantastic (and extravagant: anecdotal history says that the chateaubriand recipe called for three pieces of tenderloin in the preparation: two thinner pieces of meat charred, leaving the thick, inner pieces succulent) meals. The imprimatur of the aristocrat remains, but the name of the chef is lost to history. Chateaubriand is also a noted author: a royalist, he wrote An Historical, Political, and Moral Essay on Revolutions, Ancient and Modern, putting the Jacobins in historical context. His monumental, posthumously published autobiography Mémoires d'Outre-tombe formed a theme of Paul Auster's The Book of Illusions.... Read more
April 18, 2006
In which our hero takes a turn in which our hero takes a turn
Tupper's Self-Referential Formula and quines (even in brainfuck!). The shell-scripting page is an especially good larf. Oh my.... Read more
January 11, 2006
In which we wish you a happy birthday
Albert Hofmann turns 100 today. Most famous, perhaps, for the colourful bicycle ride he experienced after administering his synthesized hallucinogen to himself, he also fits in well to the words and sentiments of REM's song "Man on the Moon": "Albert Hofmann / on a bicycle ride / yeah yeah yeah yeah / Albert Hofmann is the chemist of shrooms / (etc) / now Albert did you ride along this street (etc) ..." I have a very handsome edition of his memoir, "LSD: My Problem Child", which is readily available online.... Read more
November 7, 2005
In which we stop Catherine the Great from cheating
Amazon's Mechanical Turk intrigues and fascinates me. Cooler (not only because one can make money) than the ESP game built by academic researchers, the Turk challenges the human to write, decipher images, select and compare, and all sorts of menial tasks that cannot quite be automated by a machine -- or perhaps already have, but require human approval to refine their decisions. Already the top results for "Mechanical Turk" are polluted with blogs referring to Amazon's API -- but the fascinating, real story can be found in Tom Standage's book and, of course, in the Wikipedia.... Read more
November 4, 2005
In which it is a selective sort of engineering
arup and co. are taking none of the blame for the designed-by-committee Millennium Bridge shenanigans: the current fashion blames the pedestrians on the bridge of collusion in causing structural instability through collective synchronisation. Not quite as dramatic as Galloping Gertie, perhaps, but frightening nonetheless.... Read more
October 25, 2005
In which the spheres have music
The Long Now Project triumphantly presented its Orrery Clock. a picture, because I like it.... Read more
October 19, 2005
In which we can tear the weaving from our loom
Scraps of papyri arrive at Berkeley, and the crocodiles in the Nile are shivering. The Tebtunis Papyri form the largest and most bewildering collection of ancient writings in the US. Though it took 105 years for the papyri to reach the campus, Berkeley was spared the long anxiety endured by Penelope, Odysseus' long-suffering wife. Berkeley didn't even know the missing material existed until three years ago. Berkeley's papyrologist, Todd Hickey, discovered the materials were stranded on a distant island called Great Britain, where they were being held by a notorious document-hoarding tribe known as Oxford dons. The bulk of the material -- much of it found in the wrappings of crocodile mummies at the ancient city of Tebtunis -- made its way to Berkeley early last century to form what campus officials say is the largest papyri collection in the Western Hemisphere.... Read more
October 16, 2005
In which we must move mountains
The New York Times has a fascinating report on the solid-waste disposal problem that results from the recent hurricanes: 22 million tons, which may require 3.5 million truckloads to haul it away. x 3.5 million... Read more
September 9, 2005
In which the new is old again
A story about urban archaeology in San Francisco contrasts with a story about the rebuilding of the Central Freeway ("Octavia Boulevard", the Road That Goes Nowhere). Other now-inland shipwrecks serve as interesting obstacles for public works projects. The new Municipal Railway tunnel extension that takes baseball fans out to SBC park goes right through the hull of The Rome, a ship's remains underground at the intersection of Market Street and the Embarcadero along the waterfront." I am embarrassed to have voted for the Octavia Boulevard project, partly because it has turned out so poorly, and partly because at the time I was mostly excited that the Central Freeway would disappear. I was wrong about the intention of Octavia Boulevard: it misses the opportunity to provide a clear, continuous surface-grade thoroughfare from south of Market Street to Geary Boulevard. Although this route is indirectly available through Gough and Frankling streets, these do not permit seamless travel from the freeway to Geary, which is something essential to moving private auto traffic to those highly residential neighbourhoods along Geary. Octavia Boulevard and the Market Street off-ramp also turn out to be strangely pedestrian- and bicycle-unfriendly: a freeway offramp touches down exactly where many pedestrians and cyclists will be walking. I cannot imagine that will be a fun intersection to negotiate during rush-hour, with cars choking the southeast corner of the off-ramp in order to turn right on to Market St (will this even be permissible? If so, chalk up another design oddity). On the other hand, I imagine that Flippers is looking forward to a boom in its business. It sits neatly at the end of the Octavia Freeway, at a t-intersection where drivers wishing to continue on Octavia need to dog-leg to the north or turn on to Hayes Street.... Read more
August 26, 2005
In which we are non-deterministic
A random link and another offer great insight into the adage that entropy "isn't just a good idea, it's the law!".... Read more
July 30, 2005
In which we praise the metric system
Pierre Mechain discovered stars as well as measurements.... Read more
March 15, 2005
Can you use it with your friends? I say yes.
20q is an online neural net that simulates the "Twenty Questions" game. It guessed with suspicious accuracy what I was thinking of. You were thinking of a tabby cat. Is it considered valuable? You said Yes, I say Doubtful. Is it brown? You said Partly, I say No. Is it a specific type? You said No, I say Yes. ... Uncommon Knowledge about a tabby cat Does it roll? I say Probably. Does it get wet? I say No. Is it gray? I say Yes. Would you find it on a farm? I say Yes. Is it spotted? I say No. Can you use it with your friends? I say Yes. Is it a geological product? I say Doubtful. Is it made of metal? I say No. Is it made of metal? I say No. Is it made of metal? I say No. Is it made of metal? I say No. Is it made of metal? I say No. Is it made of metal? I say No. Is it made of metal? I say No. Is it made of metal? I say No. Is it made of metal? I say No.... Read more
March 12, 2005
you're going to miss me when I'm gone
Fiona wrote about the animal most likely to eat you when you're dead. I can hear Roky Erickson hollerin'.... Read more
March 10, 2005
Lies, damn lies, and
gullible.info, an aptly-named blog that contains enough trivia to choke ten thousand pub quizzes.... Read more
February 23, 2005
December 24, 2004
It's on America's tortured brow
Do you want to IM with Martians? Vinton Cerf considers the possibility. NASA is already studying designs for a "Mars network" of multiple orbiting relay satellites. These satellites would be launched over a period of years, possibly starting in 2005, and the constellation would be replenished by new launches as older satellites' orbits decay. This would enable connectivity between Earth and Mars much (or even most) of the time. The frequent and relatively high-speed connectivity provided by the planned Mars network wouldn't be as "stable" from minute to minute as a terrestrial backbone.... Read more
December 3, 2004
November 25, 2004
Malady of the month
Malady of the Month features photos and a layman's explanation of a different disease each month. Syphilis, aka "The Pox", has long fascinated me. A friend called up a few months ago, saying, "I found a book and immediately thought of you." I swung by to check it out, and it was a 1950s US government publication entitled "Syphilis"; I already had a copy.... Read more
October 11, 2004
aye-POD
Moonset in Catalan. The original site has a cheery FAQ: Q13. What if I used to be a millionaire but then I believed something I read on APOD and now own only a single dented bucket? The authors also post irrational.... Read more
October 7, 2004
Carta blanca
Online maps keep getting more and more interesting. Multimap have a not-so-humble motto: "Online maps to everywhere". And the overlays they produce are very pretty. The MIT service has nice lowsrc quips about the application. Ha! Geeky fun.... Read more
September 23, 2004
To infinity and beyond!
While I admit to a love of infinity and of a certain cat, I never thought to combine the two. And a-propos of math, a research group at Berkeley will place puzzle placards on a quarter of MUNI buses. The puzzles will feature appealing math puzzles and offer rewards for correct solutions.... Read more
August 7, 2004
Riot-proof, and you know how to swim
The current issue of the University of Chicago Magazine features an article on myths that have arisen about the school: the swimming requirement; the (old) student union's namesake, Mrs Ida "Come on bring the" Noyes; and the legendary steam tunnels between Burton-Judson and the Classics Quad. Interdisciplinary, my ass.... Read more
June 10, 2004
The psycho zeta buckdown.
The twin prime conjecture and the Riemann hypothesis have long remained two of the long-standing conundrums in number theory. And now they are solvéd? And the latter for a pretty purse? Louis de Branges of Purdue University has published a paper, not yet peer-reviewed, claiming to solve the Riemann hypothesis. De Branges is perhaps best known for solving another trenchant problem in mathematics, the Bieberbach conjecture, about 20 years ago.... Read more
June 2, 2004
MIx First and Separate LAter?
separate faeces from urine; produce energy and reduce wastewater usage http://www.holon.se/folke/kurs/Distans/Ekofys/Recirk/Eng/mifsla_en.shtml http://www.wost-man-ecology.se/clearvac_duo.... Read more
May 27, 2004
Like Mercator
This online mapping tool produces interactive maps (with nearby transit stops marked!) for almost any address in the European Union.... Read more
May 26, 2004
inquotes
Syntax and semiotics are sciences, and Bob the Angry Flower is our relict, at least when it comes to the inappropriate use of quotation marks, apostrophes, and possessives (or should I write possessive's?). Spotted this stern warning on a van in Camden Town.... Read more
May 24, 2004
Errare humanum est
The collapse of the new terminal 2E at Paris' Charles de Gaulle must teach us lessons: we learn from the structural failures more than from our successes. This is the moral of Henry Petroski's excellent To Engineer is Human, in which he makes this point again and again. We must learn from this mistakes, further our understanding of structures and their failure modes. Another, more technical book on this same topic is Mario G. Salvadori's Why Buildings Stand Up; of course, when his grandmother saw the book, she said, "It'd be much more interesting to read about why buildings fall down, so he (with Matthys Levy) wrote about that, too. The Kansas City hotel disaster which figures prominently into Salvadori's and Petroski's writing also forms the plot of Paul Auster's recent Oracle Night. The tube-obsessed engineers who constructed CdG's new terminal attempted something revolutionary; the unfortunate aspect was that the structure was heavily-used and very public. To construct a tunnel in the open air, without the natural forces of the enclosing ground, is audacious.... Read more
May 21, 2004
Round up the usury suspects
Heard Muhammad Yunus, the Bengali economist and founder of Grameen Bank, speak today. His autobiography, Banker to the Poor, touches on Bangladesh's historical patriarchy, terrible fight for independence, and periodic natural disaster as sources of its contemporary poverty. Yunus is plain-spoken and inspirational: in fact, many of his stories sound too good to be true. While the economic ideas behind the bank are revolutionary, the social aspect is rooted in an almost unbelievable faith in human nature. But it works, and has worked for almost three decades; moreover, the system of microcredit he pioneered has been implemented in dozens of countries and cultures worldwide.... Read more
May 5, 2004
Lime in the cocoa-nut?
I am re-reading Robert Kanigel's evocative biography of Srinivas Ramanujan The Man Who Knew Infinity. Amongst the thrilling problems presented in the text is the case of the guavas and the monkey: "Two monkeys having robbed an orchard of 3 times as many plantains as guavas, are about to begin their feast when they espy the injured owner of the fruits stealthily approaching with a stick. They calculate that it will take him 2 1/4 minutes to reach them. One monkey who can eat 10 guavas per minute finishes them in 2/3 of the time, and then helps the other to eat the plantains. They finish just in time. If the first monkey eats plantains twice as fast as guavas, how fast can the second monkey eat plantains?"... Read more
May 4, 2004
Catalans and bears, oh my!
Perhaps not as graphically compelling as one of my all-time favourite links, the On-Line Encyclopedia of Integer Sequences sports a spiffy "webcam" for examining sequences in the database. Spiffy sequence of the day, although with a misnomer: The Catalan sequence was first described in the 18th century by Leonhard Euler, who was interested in the number of different ways of dividing a polygon into triangles. The sequence is named after Eugène Charles Catalan, who discovered the connection to parenthesized expressions.... Read more
April 23, 2004
Bargee brings mud!
The New York Times' Monica Davey has a spectacular piece on mud transplantation, from Peoria to Chicago. In Chicago, United States Steel will use the nutrient-rich mud to slather a slag heap on the South Side, making a 573-acre site habitable. Meanwhile back at the Salton Sea, another fabulously muddy area: California lawmakers, having settled with Federal agencies on plans to share water running into the Sea, now have a $730 million development plan.... Read more
April 7, 2004
Everywhere they looked (and they looked in a lot of places)
The proof is in the pudding: computers have validated Dr Thomas Hales' proof of (also known for Sir Walter Raleigh, who demanded an estimate of the cannonballs in a yay-high stack). He didn't call it face-centered cubic packing, and probably the grocers down by the corner store didn't either, but now we're closer to agreeing on the proof. ... the proof that the grocers have been right all along, and we can't even get a computer to prove it within twenty years.... Read more
April 5, 2004
... to hang from my own thread
Civil engineers are designing a steeper cliff better bridge to strike with a big barge.... Read more
February 13, 2004
Learning math at the corner store.
Yesterday I smelled something pleasantly tangy as I walked into a meeting. One of my colleagues was nestling a Wint-O-Green Life Saver candy in his mouth. According to this morning's New York Times, scientists have made another important breakthrough in the fascinating field of complex materials theory: the problem of how to most densely pack spherical or round molecules.... Read more
