Updated: 2012-10-26 16:40:35
After a brief hiatus, our roundup of the week’s best physics videos is back! We have quantum theory, Higgs updates, Iron Man suits and.. boo bubbles, whatever they are?! What are you waiting for? Hit play! The Origin of Quantum Theory (feat. Neil Turok) This is a great demonstration of Max Planck’s work in quantum [...]
Updated: 2012-10-25 18:10:09
In 2008, a fossil hunter named Frank Hadfield went for a walk among the hoodoos of Drumheller, Alberta. Up on one of these chunky sandstone minarets
studding the southern Albertan badlands, Hadfield spied what appeared to be the remains of a small carnivorous dinosaur. He called his colleague Francois
Therrien, a paleontologist at the nearby Royal Tyrrell Museum of Paleontology, to come have a look.
By itself, this was an exciting, though perhaps not momentous, find. Drumheller is located in the heart of what's known as Alberta's Dinosaur Valley, and
it got that name for a reason: ancient rivers once coursed through the landscape, their sandy bottoms preserving the bodies of hundreds of the area's
ancient inhabitants. Forty dinosaur species were first discovered there, and the valley has been a UNESCO World Heritage site for more than 30 years. But
when Therrien got to the site and he and his technicians began to saw the dinosaur out of the hoodoo, something happened that would add another feather, so
to speak, to Drumheller's cap.
While they were working on the outcropping, a chunk of it split off the main block. Examining it, Therrien saw it was laced with black streaks. The streaks
looked familiar. Like all modern paleontologists, Therrien was acquainted with the spectacular feathered-dinosaur fossils of the Liaoning beds in China,
where the idea that dinosaurs are the ancestors of birds got its biggest boost, thanks to the preservation of feathers--both the thread-like ones known as
"dinofuzz" and the more familiar shafted kind--in the silky mud of an ancient lake bottom. "If we were in China," he cracked, "we'd call those feathers."...
Updated: 2012-10-25 15:15:00
Out beyond the orbit of Mars lie fragments of worlds that might have been. Back when Earth was still forming and the moon was a molten ball—some 4.5 billion years ago—the chunks of rock and ice there never moved on to bigger things. The solar system probably would have ended up with a few more planets as large as Earth had not Jupiter’s immense gravitational sway hurled those building blocks apart before they could come together. Today more than a million remnants of that stalled genesis survive, making up the ragged asteroid belt between Mars and Jupiter.
Some 40 percent of the belt’s total mass is concentrated in just two asteroids, Ceres and Vesta—the ones that came closest to growing up. Ceres is so big that six years ago the International Astronomical Union upgraded its status to “dwarf planet,” putting it on equal footing with Pluto. Vesta, though a shade smaller, is in some ways even more deserving of the title, sharing many of the geological qualities that define Earth, Mars, and the other inner planets. And yet both asteroids were, until very recently, entirely unexplored.
“They are the most massive bodies between the sun and Neptune that have not been visited by a spacecraft,” says Marc Rayman, the chief engineer for a NASA mission dedicated to addressing that lapse.
The Dawn spacecraft—so named because it will give scientists their first close look at two relics from the very beginning of the solar system—took off from Cape Canaveral atop a Delta II rocket in September 2007. It settled into orbit around Vesta last summer; in late August it is scheduled to leave the asteroid and begin a two-and-a-half-year voyage to Ceres.
Dawn is a mission two centuries in the making...
Image: Vesta's cratered face, as seen from Dawn; the spacecraft (illustrated here) is orbiting 3,200 miles above the surface. Courtesy NASA/JPL-CALTECH
Updated: 2012-10-24 04:45:00
After SARS broke out in China in 2002, it reached 29 countries in seven months. Air travel is a major reason why such infectious diseases spread throughout the globe so quickly. And yet even with such
examples to study, scientists have had no way to precisely predict how the next infectious disease might spread through the nexus of world air terminals—until now.
In 2010 MIT engineer Ruben Juanes set out to model the movement of a pathogen from a single site of departure to junctions worldwide. If he could predict the flow of disease from a given airport and rank the most contagious ones, government officials could more effectively predict outbreaks and issue lifesaving warnings and vaccines. So Juanes and his team used a computer simulation to seed 40 major U.S. airports with virtual infected travelers. Then they mimicked the individual itineraries of millions of real passengers to model how people move through the system. The travel data included flights, wait times between flights, number of connections to international hubs, flight duration, and length of stay at destinations.
JFK International in New York—one of the world’s most heavily trafficked airports—emerged as the biggest culprit in disease spread. Honolulu, despite having just 40 percent of JFK’s traffic, came in third because of its many long-distance flights. The biggest surprise...
Image courtesy of Christos Nicolaides/Juanes Research Group/MIT
Updated: 2012-10-23 17:24:35
Asymptotia 100 Registered TEDYouth Approaching Published on October 23, 2012 in education fun science science education string theory and work 1 Comment Ack As you know , it has been an incredibly busy semester for me , but I still try to find time to tell you a bit of what is going on . Not long ago I got an email from the TED people asking me if I’d like to talk at one of their events . This event is for young people , called TEDYouth . It’ll be on November 17th . Well , this is such a good cause how can I not do this You can see the announcement of the incredible lineup” of speakers on TED’s site here I linked the photomontage they used there . I’m looking forward to being in the audience to hear some of these guys talk So of course , I now find myself a week behind where I should be in
Updated: 2012-10-22 22:55:00
Nearly a decade ago Hermann Pfefferkorn and jun Wang—scientists from opposite sides of the globe—came together to go prospecting among the granite slabs of Inner Mongolia’s Helan Shan mountain range. From nearby fossil finds, they knew the mountains preserved plants and animals that flourished long before the dinosaurs. Though the researchers had trekked the route often, this time they noticed that coal
miners had freshly exposed a gleaming white bed of volcanic rock. The rough sediment appeared to be stamped with blackened forms. When they clambered up to investigate, they realized the markings were hundreds of plant fossils. “As we split the rocks, we saw the marvelous preservation,” recalls Pfefferkorn, a paleoclimatologist at the University of Pennsylvania.
Last April, Pfefferkorn and Wang, a paleobotanist with the Chinese Academy of Sciences, described the full magnitude of the find: an entire swath of ancient swamp forest frozen in time beneath more than 20 square miles of volcanic ash. The scientists realized they could re-create, in striking detail, the swampland that would have stood before them during the early Permian period, 298 million years ago. Back then, the landscape was flat, mostly waterlogged, and thick with greenery. Animals including the Arthropleura—a nearly 10-foot-long relative of the centipede—splashed through grass-free, shallow waters, their feet skimming the spongy peat made from decomposing foliage. Dragonfly-like insects with foot-long wingspans buzzed in the humid air, and chunky primitive spiders called trigonotarbids, bearing thick black-tipped fangs, sat atop trees, says Smithsonian Institution paleobiologist Bill DiMichele. Over tufty ground covers and ferns, the brushlike tops of slim Sigillaria trees towered up to 80 feet high; they are related to club mosses and squat ground pines that today hikers trample without a thought. In patches, the forest thinned and ferny undergrowth dominated...
Illustration by Ren Yugao
Updated: 2012-10-21 15:10:00
Vast swaths of reddish-
brown pines dominate the landscape on the trails of Yellowstone National Park in Wyoming and down ski runs around Aspen, Colorado. The morbid color, by now a staple of the Rockies, comes not from fire or some exotic disease but from an insect no larger than a grain of rice—the bark beetle.
North American foresters have tracked the invasive bark beetle for centuries, but in the last 15 years its numbers have exploded. Beetles are now wiping out trees, even whole forests, at an unprecedented pace; they ravaged 9.2 million acres of forest in the western United States in 2010, according to the Forest Service, three times as much as that destroyed by fire. In British Columbia, the devastation over the last decade covers an area larger than Florida.
Until recently there was virtually nothing landowners could do to protect even small parcels of forest from bark beetles. But after a half century of detective work, a small group of scientists has come up with a novel and surprisingly effective means of defense: hijacking the beetles’ sense of smell.
Like ants and honeybees, beetles communicate via scented chemicals called pheromones, one of which warns the insects to stay away from particular trees. Now researchers are dispersing this pheromone, called verbenone, placing a molecular shield over thousands of acres of hardy green pines in western ski resorts, nature reserves, and campgrounds. “Verbenone is just fantastic,” says David Wood, a retired forest entomologist at the University of California, Berkeley. “It’s the only effective treatment, period...”
Image: Shutterstock
Updated: 2012-10-20 20:35:00
The ice-blue, 50-story office tower looming over my low-slung Queens neighborhood seems to have a weather system all its own. On a still, sultry August afternoon, a pleasant breeze snakes through its courtyard, rustling the leaves of the birch trees planted there and lofting drops of water from the fountain across the street. At other times, the mood around my behemoth is not so benign. An ordinary summer rain can be transformed into something rageful; walking through the puddles afterward, you see trash cans stuffed to overflowing with disarticulated umbrellas. And when a real storm blows through, the building whips up vortices intense enough to smash birds lethally into the windows.
Every time I walk into these freakish, localized gales, springing up while a block away there was nary a breeze, it seems like more than physics is at work. The wind feels purposeful, mysterious, even personal. It kind of creeps me out.
In a sense there truly is a grand conspiracy going on. Every storm and every gentle eddy of air traces its energy back to the solar rays—173 petawatts of energy beating down on our planet, relentlessly heating the air and stirring the atmosphere. (A petawatt is a billion megawatts. We’re in literally astronomical territory here.) That’s what I’m up against. That’s what I want to understand...
Image: iStockphoto
Updated: 2012-10-19 19:47:32
FQXi has recently issued a Request for Proposals, using money from the Templeton Foundation to fund about $3 million in grants for research on the “Physics of Information”: What is the relationship between information and reality? Can information exist without … Continue reading →
Updated: 2012-10-19 14:35:00
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Updated: 2012-10-16 16:35:00
On average, the residents of Sun City, Arizona, occupy their domiciles for a dozen years. When they depart—almost always by dying—they often leave their brains behind. The stages of physical and mental decline take them from their dream house to a hospital off Del Webb Boulevard, then to a nursing home, and finally back to the medical complex, where researchers harvest their most important organ. Hoping to do good for science, they have enrolled in the Brain and Body Donation Program of the Banner Sun Health Research Institute—widely considered the world’s preeminent brain bank.
A large base of well-
documented donors in close proximity sets the Sun City program apart from other repositories, which often have scant information about patients who may be scattered and diverse. Here, healthy, active seniors who eventually die of, say, heart disease, can be compared with others who develop neurodegenerative disorders. Because the two sets of subjects have similar backgrounds, lifestyles, and ethnic traits, changes relating to a brain disease should be easier to detect...
Updated: 2012-10-15 16:00:00
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Look. No, really look. -cvj
Updated: 2012-10-10 03:35:00
As a graduate student at Harvard University, I worked with one of the most influential behavioral scientists of all time, B. F. Skinner. Beginning in the summer of 1977, we worked together nearly every day for more than four years, designing experiments and chatting about literature, philosophy, and the latest research. Although we were 50 years apart in age, we were also friends. We saw Star Wars together, had lunch frequently in Harvard Square, and swam in his backyard pool each summer. “Fred” (from Burrhus Frederic) Skinner was the happiest, most creative, most productive person I have ever known. He was also, needless to say, quite smart.
But the septuagenarian I knew was well past his intellectual peak. One day he gave me a set of tapes of a famous debate he had had with psychologist Carl Rogers in 1962. The Skinner on those tapes seemed sharper, faster, and even wittier than the man I knew. Was I imagining this?
Recently, Gina Kirkish, a student at the University of California, San Diego, and I analyzed tapes of three comparable samples of Skinner’s speech: that 1962 debate, a 1977 debate, and a speech he gave from notes shortly before he died in 1990 at age 86. We found that the speech rate dropped significantly over time, from 148 words per minute in the first sample to 137 in the second to 106 in the third—an overall decrease of more than 28 percent.
Skinner’s memory and analytical skills were also declining during the years when I knew him. Sometimes he had no recollection of a conversation we had had only days before. When I tried to talk with him about technical papers he had published early in his career, he often didn’t seem to understand what he had written. And he had no patience for anything mathematical, even his own equations. On the other hand, Skinner was still much smarter than most of the people I knew my own age. When you fall from a high enough cliff, you remain far above ground for a very long time.
The sad truth is that even normal aging has a devastating effect on our ability to learn and remember, on the speed with which we process information, and on our ability to reason. Recent studies suggest that the total loss in brain volume due to atrophy—a wasting away of tissue caused by cell degeneration—between our teen years and old age is 15 percent or more, which means that by the time we’re in our seventies, our brains have shrunk to the size they were when we were between 2 and 3 years old. Unfortunately, most of the loss is in gray matter, the critically important part of the brain composed of neurons, the cells that transmit the signals that keep us breathing and thinking...
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Image: In an older person's brain (right), the neuronal network shrinks, the subarachnoid space widens, and mental processing slows. Courtesy of courtesy of Oregon Brain Aging Study, Portland VAMC and Oregon Health & Science University.
Updated: 2012-10-05 16:30:00
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Updated: 2012-10-05 05:27:02
At first you might feel a slight sting as the fangs enter. Then, a tingling will spread throughout your limbs. But within minutes your central nervous system will start shutting down, culminating in convulsions, paralysis, and a suffocating death. The venom of the black mamba snake, one of the world’s deadliest poisons administered by one of the world’s deadliest reptiles, can kill you within half an hour. Untreated bites have a mortality rate of 100%.
Hidden in the grim cocktail the snake carries, though, are a couple of proteins with a remarkably different effect. Research published this week in Nature has revealed two molecules in mamba venom that can eliminate pain with as much potency as morphine, suggesting an unusual new source for painkillers.
