Discoblog » Physics & Math. ’Nuff Said.

Black Box Bot Soaks Up Heat, Then Follows You Around and Keeps You Warm

Valerie Ross — Tue, 07 Feb 2012 17:26:36 +0000

When it gets cold out, staying warm usually means either cranking up the heat—and, thus, the heating bill—or piling on the sweaters and straying from the radiator’s immediate vicinity only when absolutely necessary. But your days of dashing between warm spots, or paying extra for the privilege of not, may soon be at an end. A new robot can keep you warm by saving up the heat you’ve already got until you need it.

HAGENT, as the robot is called, isn’t much to look at; it’s just a plain black cube with a couple barely visible wheels peeking out the bottom. But when HAGENT senses warmth—from an oven, a radiator, or any other heat source—it rolls over and soaks up the heat with its internal phase change material, stuff that turns liquid and stores energy when it’s heated up. Once the bot has its thermal fill, it makes its way to wherever you are and emits the stored heat. Its insides re-solidify in the process, so once it’s made your toes suitably toasty, it’s ready to do the whole thing again. In other words, it’s the automated answer to a housecat that soaks up sunlight, then curls up on your ...

High Schoolers Fold TP a Record Number of Times, Can Now Pad Resumes

Valerie Ross — Thu, 12 Jan 2012 19:48:52 +0000

High school kids armed with rolls of toilet paper usually mean there’s going to be a mess on someone’s lawn. A group of Massachusetts students, who had amassed a stockpile of more than 10 miles of toilet paper, could have been the terror of the neighborhood—had they not put their arsenal towards a more cerebral purpose: folding it 13 times. Folding toilet paper hardly sounds like an accomplishment, particularly to those of us who are long since potty trained, but try folding a spare sheet (of any paper) and see how many folds you can manage; until recently, folding paper more than seven times was thought to be mathematically impossible.

But these high schoolers (and their enthusiastic math teacher) crunched the numbers and got to folding, nearly doubling the long-assumed limit and surpassing the 2002 record of 12 folds. The resulting structure stood two-and-a-half feet tall and was made of 8192 layers of toilet tissue. Just in case 2-ply wasn’t enough.

[via New Scientist]

6 Servings of Thanksgiving Science: Ideal Turkey Diet, Black Friday Sales Tricks, Turkey-Phobia…

Valerie Ross — Wed, 23 Nov 2011 13:17:23 +0000

It’s almost Thanksgiving here the US. Before you tuck into your stuffing, pumpkin pie, and cranberry sauce, save a little room for a big helping of science. Here are a few of our favorite Thanksgiving science stories from around the Internet, detailing the research behind fattening turkeys, giving thanks, post-holiday shopping, and more:

Discovery News takes a look at what turkeys have for dinner before becoming dinner. Typical feed pellets are made of, among other things, “soybean meal, animal by-products, [and] distillers’ grains.” But a professor at the University of Missouri has developed ”the Missouri Ideal Turkey Diet,” carefully designed turkey food that costs 8 to 10 percent less than typical feed pellets while packing the same nutritional punch. Yum. As you think about what you’re thankful for this year, the New York Times offers one more thing to add to your list: the very act of giving thanks is good for you. Even a little bit of gratitude, scientists have found, makes people happier and healthier. If you’re thankful for health and happiness already, you’ve got the start of a nice little feedback cycle there. And if you’re not feeling particularly grateful, as ...

The Latest on the Great Magnetic Cow Smackdown

Veronique Greenwood — Mon, 14 Nov 2011 18:09:07 +0000

“Magnetic Cows Are Visible From Space” is a memorable headline, and writers had occasion to use it several years ago, when, after poring over satellite pictures from Google Earth, a German research team reported that cows in the images reliably lined up along the magnetic field lines that run across the Earth. The magnetic field may be invisible to us without a compass (although we have sensors in our eyes that are theoretically capable of detecting it), but various animals, including sharks and turtles, are able to sense it, and one explanation for how birds manage to navigate on cross-continent migrations is that they are steering by the magnetic field. Are cows, too, endowed with magnetic field-sensing equipment?

That first paper, in 2008, and a follow-up in 2009, which showed that cows didn’t line up when they were near high-voltage powerlines (known to distort magnetic fields), seemed to indicate that they are. But an analysis of Google Earth images by another team finds no such lining up. In a back-and-forth over the last year in scientific journals, the first team reanalyzed the second’s data and said that ...

Angry Birds TMI FTW: Better Gameplay Through Physics

Veronique Greenwood — Thu, 10 Nov 2011 16:41:41 +0000

Why just do this, when you can do…

…this, too?

Cranky flightless birds and their green porcine enemies are on every screen these days. But despite the game’s apparent simplicity, it pays to have an expert unpack the fundamental physics of the Angry Birds universe (better gameplay through physics, and all that). That expert is physics prof and graph maker extraordinaire Rhett Allain, whose rationale is summed up thusly in his first Angry Birds post:

But what about the physics? Do the birds have a constant vertical acceleration? Do they have constant horizontal velocity? Let’s find out, shall we? Oh, why would I do this? Why can’t I just play the dumb game and move on. That is not how I roll. I will analyze this, and you can’t stop me.

His latest offering over at Wired delves into what, exactly, is up with those yellow birds, which you can use to smash the piggies’ wooden structures. Turns out they have some iiiinteresting acceleration properties it would behoove you to grok…dig out your high school calculus and check it out.

Images courtesy of Rhett Allain and Wired

Computer Scientists Crack “Unbreakable” Code, Find Minutes of 250-Year-Old Secret Society

Veronique Greenwood — Wed, 26 Oct 2011 17:56:36 +0000

“Curiosity is inherited with mankind. Frequently we want to know something only because it needs to be kept secret.” Astute psychology on the part of this secret society scribe.

With the most powerful computers ever known , you’d think that modern codebreakers would have utterly smashed our forefathers’ puny ciphers. Well…no. There are quite a number of antique documents that remain mysterious, despite cryptologists’ best efforts. Code breaking still relies on good guesses and flashes of insight more than brute force.

But brute force and clever statistical analyses can help you unravel whether that guess was right in the blink of an eye, and that’s what let University of Southern California computer scientists and their collaborators unravel the text of a slender brocade-bound manuscript that had kept its secrets since the 18th century. The first words they deciphered? “Ceremonies of Initiation.”

Starting out, the team had no idea what language the enciphered text was. The carefully inscribed gobbledegook included Greek and Roman letters and abstract symbols, and for a long time the team worked on just the Roman letters, but that yielded nothing. As their analysis found that German was, by a hair, the most ...

(1) Capture Asteroid. (2) Mine It. (3) PROFIT!! (4)…KABLOOM

Veronique Greenwood — Thu, 01 Sep 2011 18:06:43 +0000

Reel ‘er in!

We all know that asteroids close to the Earth are Bad News. (Although not as bad as many would have you think.) But what if we could catch one? Bring it home? Put it in Earth orbit? Maybe mine it for some valuable minerals; do a little science; potentially, I don’t know, back a new currency? Sure, say some Chinese scientists in a paper on the ArXiv. We should go for it!

In fact, there’s a snazzy little number approaching the Earth right now, they write. It’s about 30 feet wide. Should be pretty easy to hook in, using one of a variety of techniques outlined in the paper, which include “conventional explosive, kinetic impactor and nuclear explosive,” as well as “Enhanced Yarkovsky effect, focused solar, gravity tractor, mass driver, pulsed laser and space tug.” The nuclear route may not be advisable, they opine: “Because the nuclear explosion can release a very large amount of energy, the result may be a fragmentation of the target NEO.” Better to go with the kinetic imapactor, they decide. A little tap to the ol’ asteroid, and it will accelerate just enough to get stuck orbiting ...

The Plane Truth: Boarding by Rows Is the Worst Possible Way, Says Physicist

Joseph Castro — Mon, 29 Aug 2011 19:17:13 +0000

Let’s face it: boarding an airplane with luggage is just downright frustrating. Not only do you have to puzzle out how you are going to wrestle your carry-on bag into the aircraft’s tiny overhead compartment, but you have to do it while trying not to get swept away by the tugging current of other passengers.

“OK, everybody count off!”
Courtesy of Steffen, arXiv

But surely not all boarding procedures are created equal—simply boarding the plane back to front would be the easiest and most efficient method, right? Wrong. In fact, boarding by sequential rows is the worst possible approach (pdf), according to a new study by physicist Jason Steffen of the Fermilab Center for Particle Astrophysics.

Steffen tested the efficiency of several different boarding procedures by sending 72 luggage-toting passengers into a movie-set Boeing 757. Among the boarding techniques tested was the zone/block style, where passengers fill the plane back to front, one large group at a time; WilMA, or Window, Middle, then Aisle (how the “l” got where it did is a mystery); and Steffen’s own procedure (imaginatively called “the Steffen method”), which incorporates both the other two techniques (see chart).

Steffen timed ...

Scientists Solve Switzerland’s Biggest Problem: Upset Stomachs on Tilting Trains

Veronique Greenwood — Fri, 05 Aug 2011 19:25:47 +0000

If you’re turning green, it’s not the scenery’s fault.

As you may or may not know, Switzerland, land of chocolate, cheese, and cuckoo clocks, is also the land of trains. More than 1,800 miles of track crisscross the quaint alpine utopia, carrying 347 million passengers per year and maintaining the punctuality of a Stepford wife. That’s some serious trainage.

Some of those trains, unfortunately, are making people trainsick. And the Schweizerische Bundesbahnen, the Swiss train authorities, just wouldn’t stand for that. They asked some scientists to get to the bottom of it.

The problem trains are a class of vehicles that tilt by 8 degrees as they go around curves, preserving their speed by compensating for centripetal force. Something about those tilts was putting passengers off-kilter, so a team of Swiss and American neurologists attached accelerometers and gyroscopes to a test train and to the heads of passengers, whom, one hopes, were compensated for consenting to their unusual headgear.

A tilting train in action.

Usually, the tilt starts with the first train car that hits the curve, then propagates through the later cars. It’s also rather slow, so passengers’ heads get tipped ...

Fore! Golf Game Lets You Frolick on Saturn’s Moons

Veronique Greenwood — Mon, 27 Jun 2011 16:29:52 +0000

This takes location golfing to a new level.

If 18 holes on Kauai or Tenerife is old hat, grab your clubs and head to Saturn’s moons.

The NASA team behind the Cassini orbiter periodically release troves of gorgeous images of Saturn and its dozens of moons, revealing the gouges on Enceladus and the lakes of Titan. The drool-worthy vistas just beg to be explored, and you can now do just that with a nifty little Flash game developed by Diamond Sky Productions called Golf Sector 6. The game takes players through several 9-hole courses across a variety of Saint-Exupéry-esque moons, whose cratered surfaces are patched together from Cassini’s images. As Saturn drifts by in the background, you can relax, put your feet up, and bat a small pink ball toward the hole with your mouse. But beware of that pesky escape velocity: it’s different on every moon, and it’s way, way less than Earth’s.

The trick of the game is getting used to the gravity of each of these moons. While the team has made some sacrifices in accuracy for the sake of playability—Saturn’s pull on the moons’ gravitational fields is excluded, ...

“Magnetic” Boy Is Probably Just “Plump-and-Sticky” Boy

Patrick Morgan — Tue, 24 May 2011 12:42:12 +0000

Spoons. Frying pans. Industrial-sized irons. The blogosphere has been awash lately with the eclectic mix of objects that stick to a six-year-old Croatian boy’s stomach. In an unfortunately serious story, CBS reported that “Magnet” boy can carry upwards of 55 pounds of metal on his chubby little frame. What they forget to mention is that the boy’s “magnetic” abilities miraculously extend to mostly non-metal objects too, such as plastic TV remote controls and cell phones.

It also doesn’t help that little Ivan Stoiljkovic’s family apparently didn’t think human magnetism was odd enough: They claim that his hands radiate a special kind of heat that allows the boy to soothe “his grandfather’s stomach pains” and “the pain of a neighbor who hurt his leg in a tractor accident.” As for Ivan himself, his cuts apparently heal “very quickly,” leaving no trace of a scar (of course, it probably has nothing to do with the fact that younger skin just heals faster, with its greater elasticity and stronger connective tissues).

As Nature’s Barbara Ferreira so astutely points out, “If Ivan had indeed magnetic powers, he wouldn’t have the need to bend slightly backwards to keep the items stuck to his ...

Small Particles Can Flow Up Waterfalls, Say Tea-Drinking Physicists

Veronique Greenwood — Tue, 17 May 2011 16:45:04 +0000

When the height is right, tea leaves zip up the
waterfall and go for a swim in the upper container.

It’s not just salmon that can leap nimbly up waterfalls, according to a new study in the physics arXiv: wee particles like tea leaves and industrial contaminants can flow upstream if conditions are right.

Cuban scientists first noticed this strange phenomenon while brewing yerba mate by decanting pure water from one container into another containing the tea leaves. Mysteriously, tea leaves sometimes appeared in the water container.

They investigated and found that when a waterfall from one container into another is no more than a centimeter high, the water’s flow generates a counterflow along the edges of the channel that goes in the opposite direction, drawing chalk powder and tea leaves up into the higher vessel. While scientists knew that such counterflows could form, the idea that they might persist even after the water goes over a waterfall is a kooky new take on it.

This map of the velocities of particles on the water’s
surface shows the counterflow in red and the main flow in blue.

It’s not all fun and water ...

Finally, a Home Decorator Everyone Can Afford: a Computer Program

Veronique Greenwood — Wed, 04 May 2011 18:36:12 +0000

Next time you get the urge to redecorate, hire an algorithm. A new program developed by computer scientists can take a jumble of furniture and arrange it into a variety of realistic configurations using just a few simple rules, like “the TV must be visible from the couch,” “the lamp should be near the desk,” and (important, but oft-overlooked) “doors must be able to open.” You can then choose your favorite arrangement without having to heave the couch across the room more than once.

Visibility constraints throw out any arrangements
where important views are blocked.

The program, called Make It Home, uses basic spatial rules gleaned from examples of pleasingly furnished rooms to come up with its interior designs. It first extracts the rules governing example rooms, including furniture spacing, the existence of pathways between doors, and the relationships between objects like the DVD player and the TV, which must be near each other, or the TV and an armchair, which must maintain a line of sight. Then it whips through successive iterations of the room to be organized, automatically adjusting each version’s failings until all the criteria are satisfied. Watch the video above ...

Gyroscopic Wheels Don’t Keep Bikes Upright? Back to the Drawing Board…

Veronique Greenwood — Mon, 18 Apr 2011 19:28:54 +0000

Take your hands off the bicycle handlebars and your bike won’t notice. Hop off and give it a shove, and chances are it’ll keep skimming along all on its own (as long as you don’t push it over en route to your faceplant). Ever since bicycles were invented in the 1860s, people have been wondering: what makes bikes so spookily stable?

Popular explanations are that the spinning wheels behave like gyroscopes or that the front wheel making contact with the ground just behind the steering axis stabilizes the bike. But take both of those properties away, researchers reporting in Science ($) have found, and the bike still rolls merrily onward.

The team built their own bicycle with extra wheels that rotated in the opposite direction to cancel out the gyroscopic effect and with a steering axis that’s behind the front wheel, and found that even that was not enough to knock the bike off balance. When graduate students tried to tip it over, it steered into a turn and recovered.

So what is keeping the bike up? A great sum-up at ArsTechnica explains that the answer is: we’re still not really sure. While the math is clear, ...

“Einstein’s Pedometer” Tracks Subtle Benefit of Exercise: How Much Time Slows as You Move

Valerie Ross — Tue, 12 Apr 2011 13:46:46 +0000

I feel younger already!

If all those vague exercise benefits like heart health and improved mood aren’t enough to get you moving, maybe this will be: By taking that morning stroll, you’re slowing down the rate at which you’re aging and netting yourself extra time—whole picoseconds of it. And you know it’s true, because Einstein said so.

A corollary of the special theory of relativity, called time dilation, says that time will pass at a slower rate for something moving compared to something standing still; the faster the moving thing (in this case, you) moves, the more the rate at which time passes slows. So, you’ll age more slowly meandering around your neighborhood at three miles an hour than you would back home on the couch, and even more slowly if you up that walk to a jog.

There is, of course, an app for this, called Einstein’s Pedometer. It tracks your location via your iPhone’s GPS, does some fancy math on it, and voila, tells you how much time you gained. Just make sure you wear some sunscreen while you’re out for your stroll; you don’t want any wrinkles ...

How Cold-War Nuclear Tests Are Helping Heart-Disease Patients

Veronique Greenwood — Sat, 09 Apr 2011 19:11:44 +0000

Should we be strapping these to our torsos?

We’re all a little bit radioactive now. Thanks to atom bomb tests in the mid-20th century, it’s possible to use radioactive (but harmless) carbon-14 to date not only bristlecone pines and putative Noah’s Arks but also, in a recent Karolinska Institutet study, Grandma and Grandpa’s artery fat.

The technique used in this study—radiocarbon dating—is widely employed by archaeologists and geologists to determine when organisms like fossilized trees or plants lived. All organisms absorb carbon-14 along with normal carbon-12 in a ratio that mirrors how much of each type is present in the atmosphere. (Carbon-14 is produced naturally in the upper atmosphere by cosmic rays, and then mixes throughout the atmosphere and into the oceans.) When an organism dies, the carbon-14 starts to decay at a known rate—half the atoms become nitrogen-14 in about 5,700 years—and the amount left in the tissue when it’s dug up can be used to back-calculate its age.

The above-ground atom bomb tests of the Cold War era raised the amount of carbon-14 in the air; after the tests stopped, atmospheric radiocarbon declined at a very precisely recorded rate. Using this information, scientists ...

Mentos Is to Diet Coke as Coffee Filter Is to Guinness?!

Jennifer Welsh — Thu, 10 Mar 2011 13:36:57 +0000

The SATs might have made you hate analogy problems, but this one sure is tasty.

That clangy thing taking up space in the bottom of your Guinness or Tetley’s can might soon be done away with and replaced by a coffee filter.

The ball inside the Guinness can, called a widget, contains a pocket of nitrogen gas held under pressure. When some lucky person opens the can, the pressure is released and the gas shoots out into the beer through a small hole and creates the foam.

You may now be thinking, Wait a minute—most beers seem to have plenty of gas bubbles even without some fancy widget. The thing is that Guinness and similar brews need the widget because nitrogen bubbles are smaller than those filled with carbon dioxide, the bubbling gas in other fizzy drinks. The small nitrogen bubbles make Guinness’ foam deliciously thick and creamy, but it’s harder to get the gas to come out of solution. The widget forces lots of excess nitrogen into the beer, setting off a well-timed bubble eruption.

But the widget is not the only way to send nitrogen bubbles cascading upward. In normal ...

An Entirely Possible Legend: Vikings Steered Ships Using “Sunstones”

Patrick Morgan — Mon, 31 Jan 2011 15:59:49 +0000

You might think seafaring Vikings–who traveled hundreds of miles on rough seas between 750 and 1050 AD–would be adrift on cloudy days: not only did they lack compasses, but they were often traveling so far north that the sun never set, and thus couldn’t use stars to navigate. But scientists are finding new evidence to support the existence of what was once considered a mythical navigational tool: the sólarsteinn, or sunstone.

It all starts with an Icelandic legend about a man named Sigurd. As Nature News reports:

The saga describes how, during cloudy, snowy weather, King Olaf consulted Sigurd on the location of the Sun. To check Sigurd’s answer, Olaf “grabbed a sunstone, looked at the sky and saw from where the light came, from which he guessed the position of the invisible Sun.” In 1967, Thorkild Ramskou, a Danish archaeologist, suggested that this stone could have been a polarizing crystal such as Icelandic spar, a transparent form of calcite, which is common in Scandinavia.

Knowing that our atmosphere can scatter sunlight and polarize ...

It’s the End of the Kilogram as We Know It (And I Feel Fine)

Patrick Morgan — Tue, 25 Jan 2011 17:32:35 +0000

The speed of light may define a meter and atomic clocks may define a second, but a century-old cube of metal still defines the kilogram–at least, until scientists give this antique lump a 21st-century makeover.

As far as the kilogram is concerned, the year is still 1879, but scientists are meeting in London this week to discuss a change for this humble unit. As the Guardian reports:

“The kilogram is still defined as the mass of a piece of platinum which, when I was director of the International Bureau of Weights and Measures, I had in a safe in my lab,” said Terry Quinn, an organiser of today’s meeting. “It’s a cylinder of platinum-iridium about 39mm high, 39mm in diameter, cast by Johnson Matthey in Hatton Garden in 1879, delivered to the International Committee on Weights and Measures in Sevres shortly afterwards, polished and adjusted to be made equal in mass to the mass of the old French kilogram of the archives which dates from the time of the ...

Booze-Soaked Superconductors Provide Hot Physics Results

Shannon Palus — Tue, 18 Jan 2011 12:34:17 +0000

A paper that explores the unlikely coupling of warm wine and the electric properties of iron is currently making its rounds on the media circuit—leading us to conclude that people get excited about science when there is alcohol involved.

“Drunk scientists pour wine on superconductors and make incredibly discovery,” declares the (slightly inaccurate) headline on io9. “’Tis the season to be pickling your liver in alcohol,” announces the (slightly irrelevant) opening line of a CNET article.

The researchers’ experiment—led by Keita Deguchi of the National Institute for Materials Science in Japan—involved first submersing an iron alloy in various hot alcoholic beverages, and then finding the temperature at which the treated alloy starts to display superconducting properties. A superconductor is a material that has no electrical resistivity, allowing electrons to flow through it with essentially zero friction.

The paper abstract, which was published on arXiv, gives an overview of the experiment’s findings and method (although there’s no mention of beverage consumption that might have inspired these scientific antics):

“We found that hot commercial alcohol drinks are much effective to induce superconductivity in FeTe0.8S0.2 compared to water, ethanol and water-ethanol ...

Thunderstorms Shoot Beams of Antimatter Into Space. Really!

Eliza Strickland — Tue, 11 Jan 2011 18:15:47 +0000

In Greek mythology, Zeus hurled thunderbolts down from Mount Olympus whenever some uppity mortal or ravaging monster dared distract him from his carousing. New research suggests this mythological god-king would have had another weapon at his disposal as well: beams of antimatter.

Researchers working with the Fermi space telescope made the discovery while examining the gamma-ray flashes that thunderstorms are known to produce. (The multitasking Fermi can observe everything from gamma ray bursts in the most distant reaches of the universe to terrestrial phenomena.) The high-energy gamma-ray flashes are thought to be caused by the electrical fields produced during lightning storms.

The new study, presented at the ongoing meeting of the American Astronomical Society, suggests that these gamma-ray flashes create both electrons and their antimatter counterparts, positrons. When two of these opposing particles meet up they annihilate each other and cause another blaze of gamma rays, with a particular signature that Fermi can detect.

In a video about the findings, NASA explains that Fermi was traveling over Egypt on December 14, 2009 when it detected this signature–but the only active thunderstorm was in Zambia, too far away for Fermi ...

How to Repel Pirates? Blast Them With a Laser Cannon

Eliza Strickland — Mon, 10 Jan 2011 18:03:18 +0000

A shaft of green laser light spears out from a cargo ship, targeting a small skiff bobbing in the ocean almost a mile away. The armed miscreants aboard the skiff take one look at the dazzling light and shield their eyes with cries of distress. How can these pirates attack if they can’t see?

That’s the idea behind an anti-pirate laser cannon being developed by a UK defense company in response to the increase in hijackings off the coast of Somalia. The laser would be used in conjunction with ships’ high-frequency surface radars that detect the small vessels used by Somali pirates, and it would function as a kind of warning shot across their bow. New Scientist reports that the laser isn’t intended to fry pirates to a crisp, nor even to blind them forever:

“This is very much a non-lethal weapon,” says Bryan Hore of BAE Systems in Farnborough, UK, where the system was developed. By taking into account the range of the target, as well as the atmospheric conditions, the system can automatically regulate the intensity of the laser beam to ensure there is no ...

Building an Ancient Greek “Computer” out of Lego

Jennifer Welsh — Fri, 10 Dec 2010 21:41:15 +0000

Nature editor Adam Rutherford wanted to see how a 2,000-year-old astronomical computation machine–called the Antikythera Mechanism–works. So he set Apple software engineer Andy Carol to the task of building one, using one of the most sophisticated construction systems humanity has ever devised: Lego. It took 30 days and 1,500 Lego Technic parts.

The gear-based machine was discovered in the early 1900s in a wrecked Roman merchant ship. Even after a century of study, it took the invention of CT scans to reconstruct the corroded device’s inner workings and understand how the complex machine operates, explains Nature:

The device … contained more than 30 bronze gearwheels and was covered with Greek inscriptions. On the front was a large circular dial with two concentric scales. One, inscribed with names of the months, was divided into the 365 days of the year; the other, divided into 360 degrees, was marked with the 12 signs of the zodiac.

It is the oldest known computing device, aka “computer.” In 2008 researchers discovered that the ancient Greeks used the device to not only calculate when eclipses would happen, but also to set the schedule for the Olympic Games.

Carol ...

Big Scientists Pick Big Science’s Biggest Mistakes

Jennifer Welsh — Tue, 23 Nov 2010 23:07:42 +0000

Earlier this week Richard H. Thaler posted a question to selected Edge contributors, asking them for their favorite examples of wrong scientific theories that were held for long periods of time. You know, little ideas like “the earth is flat.”

The contributor’s responses came from all different fields and thought processes, but there were a few recurring themes. One of the biggest hits was the theory that ulcers were caused by stress—this was discredited by Barry Marshall and Robin Warren, who proved that the bacteria H. pylori bring on the ulcers. Gregory Cochran explains:

One favorite is helicobacter pylori as the main cause of stomach ulcers. This was repeatedly discovered and then ignored and forgotten: doctors preferred ‘stress’ as the the cause, not least because it was undefinable. Medicine is particularly prone to such shared mistakes. I would say this is the case because human biology is complex, experiments are not always permitted, and MDs are not trained to be puzzle-solvers—instead, ...

Amateur Cryptographers Go Gaga Over New Kryptos Clue: B-E-R-L-I-N

Jennifer Welsh — Mon, 22 Nov 2010 19:45:33 +0000

To mark the 20th anniversary of his “Kryptos” sculpture, and its lingering mystery, sculptor Jim Sanborn has released a clue to deciphering the message engraved on the statue.

“Our work is about discovery — discovering secrets,” said Toni Hiley, director of the C.I.A. Museum. “And this sculpture is full of them, and it still hasn’t given up the last of its secrets.” [The New York Times]

In 1999 three of the sculpture’s four sections were confirmed solved by computer scientist and amateur code-breaker James Gillogly. They contain historical references and cryptic sayings. Twenty years later, the remaining section, 97 characters long, is still unsolved.

And Jim Sanborn, the sculptor who created “Kryptos” and its puzzles, is getting a bit frustrated by the wait. “I assumed the code would be cracked in a fairly short time,” he said, adding that the intrusions on his life from people who think they have solved his fourth puzzle are more than he expected. [The New York Times]

To help the obsessed along in their search, Sanborn told ...

LHC Particle Physicists to World: Our New Album Drops December 6th

Jennifer Welsh — Wed, 17 Nov 2010 16:50:32 +0000

The particle physicists at the ATLAS experiment at the Large Hadron Collider aren’t just searching for the elemental forces of the universe; they are also looking for a #1 Christmas single.

Several groups of physicists-turned-musicians from ATLAS are gearing up for the release of their first tracks under the “Neutralino Records” label. The label is named after the hypothetical particle, the neutralino, which is predicted by supersymmetry and might even make up the universe’s dark matter.

Executive producer (and physicist) Christopher Thomas told Discoblog that the music club at CERN, the organization that runs the LHC, is pretty active, but the ATLAS group was motivated to make an album to “show there’s another side to physicists. And maybe a bit of ‘hey, look what I can do!’”

Samples of the songs can be heard at the website for the double CD, titled Resonance. Nineteen different musical groups participated in the creation of the album, which contains a variety of original and cover songs, explains the press release (pdf):

The album features a wealth of new songs: the highlights include an original blues song about ...

For Bees, Solving Tricky Math Problems Is All in a Day’s Work

Jennifer Welsh — Thu, 28 Oct 2010 16:23:42 +0000

Having a bee brain might not be so bad after all, since new research shows that bees are faster than supercomputers when it came to solving one of those dreadful “word problems” from (probably very advanced) high school math class.

Co-author Mathieu Lihoreau explained the significance of this discovery in a press release:

“There is a common perception that smaller brains constrain animals to be simple reflex machines. But our work with bees shows advanced cognitive capacities with very limited neuron numbers.”

The problem is called the traveling salesman problem, and the bees’ lives actually depend on solving it every day. The traveling salesman needs to visit a number of cities in the shortest amount of time, without repeating a visit. The traveling bumblebee needs to visit a number of flowers everyday, while expending as little energy as possible. Queen Mary University of London researcher Lars Chittka explained in the press release why studying bees’ habits is important:

“Such traveling salesmen problems keep supercomputers busy for days. Studying how bee brains solve such challenging tasks might allow us to identify ...

Einstein & Air Miles: Do Frequent Fliers Age at a Different Rate?

Eliza Strickland — Mon, 25 Oct 2010 15:21:10 +0000

By Valerie Ross

You’re squeezed into a middle seat, two rows from the back of the plane. It’s barely two hours into your cross-country flight, though you’d swear it’s been longer. Does it just seem like the minutes of your trip are crawling by — or does time actually pass more slowly for people who are mid-flight than for people on the ground?

Many of us have heard the idea that time doesn’t pass at the same rate for everyone. It’s a common narrative in science fiction, one that has its roots in Einstein’s theory of relativity. The story starts, let’s say, with two twins, one of whom stays on Earth while the other clambers aboard a rocket that’s making a round-trip journey, at a substantial fraction of the speed of light, to a planet in a not-too-distant solar system. When the traveling twin returns to earth, he’s aged more slowly, and now he’s younger than the twin who stayed behind.

This familiar — and paradoxical — plotline comes from a particular tenet of relativity theory known as time dilation. It predicts that a fast-moving clock will tick at a ...

Video: The Physics of How a Wet Dog Shakes

Eliza Strickland — Fri, 22 Oct 2010 16:25:47 +0000

“Many furry mammals engage in oscillatory shaking when wet.” Translation: When a dog comes in from the rain, it engages in a body-twisting, jowl-flapping shake that sprays water over the living room. But exactly what kinds of oscillations are required to make the water droplets scatter? Thankfully a team of curious researchers decided to study the physics of that motion.

In the abstract posted on ArXiv, Andrew Dickerson of the Georgia Institute of Technology and some colleagues explain that they attacked the question via high-speed video and fur-particle tracking:

As you can see from the data in the video, the research raises further questions. Their mathemathical model is based on the idea that surface tension holds the water droplets to the animal’s hair, and that centripetal forces from the shaking have to exceed that surface tension in order to free the water. This implies that smaller animals (or as they might say, animals with a smaller radius) have to shake faster in order to get dry, a prediction borne out by observations of everything from mice to bears. But when the researchers plotted the data on a graph, it didn’t quite conform to their predictions.

Technology Review, where we first saw ...

This Is What Happens When a Physicist Reads “Goodnight Moon”

Eliza Strickland — Mon, 18 Oct 2010 17:54:01 +0000

Goodnight moon, goodnight room. Goodnight frogger, goodnight super-analytical blogger.

Chad Orzel of the physics blog Uncertain Principles has had plenty of time to contemplate the beloved children’s book Goodnight Moon in the course of bedtime readings with his toddler. And he got to wondering, just how long does it take the book’s bunny protagonist to say goodnight to all the objects in the room? And could a physics blogger figure it out from eyeballing the moon’s rise through the sky during the course of the story?

Happily, yes. Go read the full post for the math of the moon’s passage through the sky; we’ll skip to the results and tell you that Orzel puts the figure at about 6 minutes. But there’s a hitch: The clocks shown in various pictures of the bunny’s room instead show that one hour and 10 minutes have elapsed. There are only two possible explanations, Orzel says:

These two methods clearly do not agree with one another, which means one of two things: either I’m terribly over-analyzing the content of the illustrations of a beloved children’s book, or the bunny’s bedroom is ...