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Showing posts from 2011

From Pen to Paper

Researchers deconstruct the physics of a revered centuries-old process: writing with a fountain pen.

Image Credit: János Fehér

Wetting a fountain pen to compose a thank-you note is a grand way to express gratitude for a holiday gift, yet we often don’t give a thought to what happens when ink moves from pen to paper. But for a team of South Korean and American scientists, the medium is more important than the message -- and can even provide new insights into ancient biological systems.

Evolution of Icicles

As the holiday season winds down, the weather in many parts of the world remains frightful. In particular, large, sharp icicles often form on gutters, trees and vehicles. Icicles are usually harmless reminders of winter, but they can present huge problems, especially for utility workers faced with power lines that fail under the weight of ice.

In a recently published article on NewScientist, author Michael Brooks explores the applications of physics research on icicle formations. With a better understanding of how icicles grow, scientists hope to provide applicable information for architects, utility workers and even Hollywood CGI specialists.

Sticky Physics

As anyone can tell you, certain liquids, like water, will usually fall in droplets while others, such as honey, will slowly slide to the ground in a long filament. The key differences between these two liquids are viscosity and surface tension, and scientists have conducted a new experiment to better understand these differences. Volcanoes, ink-jet printers, and archer fish—who use their mouth as a sharpshooting water pistol to hunt prey—all take advantage of the properties of liquid filaments and droplets.

How the Engineers Stole Christmas

How the Engineers Stole Christmas
This is an internet meme from a Christmas long, long ago. Our younger contributors, [yes, I'm talking to you Hyperspace] probably haven't seen it before. I hope that those of you who have, hearken back to your internet youth, and those of you to whom this is new, get a good Fermi problem chuckle.
So while you you stay up this evening listening for the sound of reindeer hooves clicking on your roof, here is some physics to ponder.

Happy Holidays From Science!

Understanding Deadly Ice Avalanches

An ice skating phenomenon might explain the snowball effect behind icy avalanches.

Tumbling ice particles collide and melt, accelerating this mini-avalanche. Credit: Barbara Turnbull | University of Nottingham
(ISNS) -- The same physics behind ice skating may explain why massive ice avalanches can develop so quickly according to new research.

In 2002, a small disturbance on a mountain slope in the Russian Republic of North Ossetia set off a deadly ice avalanche, engulfing two glaciers en route to unsuspecting villagers. The destruction started with the collapse of 100 million cubic meters of ice and rock, which eventually stormed through a river valley toward villages at 175 miles per hour. Over 100 villagers were killed, and similar avalanches in the Alps and in North America have threatened local populations over the past few years.

Top Ten Physics Buzz Stories of the Year

The end of the year is fast approaching and us here at PhysicsBuzz went back through all our posts of the last year and pulled out our biggest hits of 2011.

10) Uncovering Da Vinci's Rule of the Trees: Scientists test Leonardo Da Vinci's rule that a tree branch splits into two limbs of combined equal thickness, and it turns out the original Renascence Man was right!

9) Newsflash: Tachyon Neutrinos Could be the Discovery of the Century: CERN reports that they have evidence of neutrinos traveling faster than the speed of light, supposedly breaking the cosmic speed limit.

Earth-like Exoplanets Found

For the first time, scientists have discovered Earth-sized planets around a sun-like star using NASA's Kepler space observatory. Although the planets are too hot for life as we know it — temperatures on the two new planets range from 800 to 1,400 degrees Fahrenheit — they are the smallest exoplanets found around a star similar to our own.

A chart comparing the sizes of the two newly found planets, Earth and Venus. Image Courtesy NASA/Ames/JPL-Caltech.

Basketball Physics

December 25th is a day of celebration for many people, but this year an unexpected group will be celebrating: basketball fans. After months of arguing, players and owners finally agreed on new terms, and the 2011-12 season will start on Christmas day. In honor of next week's tip-off, we've collected a few tidbits of basketball physics from around the web. 

Over the past year, Wired's Dot Physics blog has been running a series of posts about probability and basketball shots. In one of the earlier posts, physicist Rhett Allain ran computer simulations of the amazing basketball shot seen in the video above. In the video, the shooter launched the ball from a 140-foot perch on a monument into a basket below. Allain wanted to know if the shot was real or fake.

Why NHL Goalies Prefer Wooden Sticks

Goalies in the National Hockey League overwhelmingly continue to use wooden sticks largely indistinguishable from those used decades ago by their mask-less predecessors.

Credit: Hakan Dahlstrom |

Compared with state-of the-art composite materials favored by the other players on the ice, the age-old wooden material dampens the sting of vibrations more effectively, making it simply more comfortable for goalies to wield a wooden stick.

Scramjet Setbacks Motivate Research

Traveling at speeds exceeding 3,800 mph, the X-51a Waverider, a joint project between the US Air Force and Boeing, could go from from New York to London in under an hour – if it doesn’t crash that is. A recent test of the scramjet-powered vehicle this summer proved unsuccessful, but new research may open the door to safe flight at hypersonic speeds, more than five times the speed of sound.

An artist's conception of the Boeing X-51a Waverider. Image Courtesy US Air Force.

Scramjets achieve such high speeds because of their unique air-breathing design. As opposed to traditional jets, scramjets use air from the atmosphere to ignite their fuel, providing thrust. Because scramjets capitalize on rapidly-moving air to produce thrust, they don’t need heavy fuel tanks to fly.

Happy Holidays From the Physics Buzz Team!

The Physics Buzz Team wishes all of you a wonderful holiday season. Hope you enjoy our little holiday "performance."

Hidden Messages in Beautiful Patterns

This week on the physics buzz podcast, scientists in Lithuania have used the science of self-organizing patterns to conceal top secret messages. Self organizing patterns are patterns which emerge from a system, but are not imposed on the system by any controlling force. Individual subunits (like the pigment cells in zebra skin, or termites in a colony) do their own thing with a basic set of instructions. The individual actions of these subunits unintentionally add up to gorgeous works of art, which can also give evolutionary advantage to some organisms. Here are some examples of self organizing patterns in nature - artwork without an artist.
Zebra stripes:
Cone shells (amazing images by Richard Parker):

The tunnels inside a termite nest:
Even flocks of birds operate under the principles of self-organizing patterns:

Here is a slideshow with a basic explanation of self-organizing patterns, and some more great examples.

Particle Physicists Report 'Intriguing Hints' of Higgs Boson

Long-sought particle not conclusively detected yet, but researchers may have found its hiding place.

CMS proton-proton collision events in which 4 high energy muons (red lines) are observed. The event shows characteristics expected from the decay of a Higgs boson but is also consistent with background Standard Model physics processes. Credit: Copyright: 2011 CERN

Physicists in Europe today reported possible signs of the Higgs boson, a missing piece in the particle-physics puzzle long suspected of giving elementary particles -- such as electrons and quarks -- their mass.

Software Helps Blind Student Learn Physics

Physics can be very difficult to learn, but imagine how much harder it would be if your textbook had numerous errors and typos. For Amanda Lacy—a computer-science major at Austin Community College—an inadequate digital textbook almost made her drop out of her physics class. With the help of a dedicated professor and some new computer software,however, she earned an A in the class and regained her enthusiasm for physics according to a recent article from the Chronicle of Higher Education.

Image Courtesy Christophe Moustier.

Another Ghost Particle?

Neutrinos, though ghostly and very difficult to detect, have been solving physics mysteries since 1930. Now an even more ghostly fourth neutrino may solve discrepancies involving the three known varieties.

Physicist Wolfgang Pauli first proposed the existence of the neutrino to account for mysteriously missing energy, momentum and spin in radioactivity measurements. Although a neutrino would conveniently solve the experimental problems, the properties of the particle led Pauli himself to bet a case of champagne that it would never be detected.

Physics of Noise-Cancelling Headphones

During the holiday season, many people are frantically travelling across the country to visit friends and family. That means long lines, big crowds and delays—stress abounds. Whether traveling by plane, bus or train, background noise can prevent any relaxing moments. So many travelers turn to noise-cancelling headphones when travelling, and there's some interesting physics behind these high-tech devices.

Noise-cancelling headphones can be broken down into two main groups: passive and active. Passive headphones simply reduce background noise by using insulating materials to prevent external noise from entering the ear. Active headphones, on the other hand, are a little more complex.
I still remember the first physics problem I tried to solve, though at the time I didn't even know what the word physics meant. I spent many a family road trip pondering this question, but my 6 year old brain could never quite find an answer. It popped back into my head during a recent road trip from Santa Fe to Salt Lake City. Finally I think my much older brain managed to solve the mystery.

Where Legos and Particles Collide

Weighing over 7,000 tons, the ATLAS experiment at CERN's Large Hadron Collider measures collisions between protons traveling near the speed of light. And now it has its own place in the world of large Lego models. One dedicated researcher has built an intricate replica of the ATLAS experiment out of 9,500 Lego pieces.

The Lego replica is 50 times smaller than the actual 7,000 ton detector. Image Courtesy Sascha Mehlhase.

Sascha Mehlhase, a postdoctoral researcher working on the ATLAS experiment, designed the model as part of an outreach project. Impressively, Mehlhase's replica captures all of ATLAS' intricate parts. Just building the initial 3D model took 48 hours, and then Mehlhase assembled all of the pieces in 33 hours.

Voyager 1 Reaches "Cosmic Purgatory"

As the farthest man-made object from Earth, Voyager 1 is no stranger to the unknown. Now it has reached an area with almost no solar wind as it makes its departure from our solar system's boundary.

Voyager 1 has reached a new zone on the edge of our solar system called the stagnation region. Image courtesy NASA/JPL-Caltech

In the Quantum World, Diamonds Can Communicate With Each Other

Researchers working at the Clarendon Laboratory at the University of Oxford in England have managed to get one small diamond to communicate with another small diamond utilizing "quantum entanglement," one of the more mind-blowing features of quantum physics.

The vibrational states of two spatially separated, millimeter-sized diamonds are entangled at room temperature by scattering a pair of strong pump pulses (green). The generated motional entanglement is verified by observing nonclassical correlations in the inelastically scattered light. Credit: Dr. Lee and colleagues, Image Copyright Science AAAS

Entanglement has been proven before but what makes the Oxford experiment unique is that concept was demonstrated with substantial solid objects at room temperature.

Uncovering Da Vinci's Rule of the Trees

Wind may be behind Leonardo da Vinci's long-standing 'rule' for tree growth.

Image Credit: cjn/ISNS/Erik Jacobson

As trees shed their foliage this fall, they reveal a mysterious, nearly universal growth pattern first observed by Leonardo da Vinci 500 years ago: a simple yet startling relationship that always holds between the size of a tree's trunk and sizes of its branches. A new paper has reignited the debate over why trees grow this way, asserting that they may be protecting themselves from wind damage.

What’s the Higgs Boson Worth?

It might seem like a simple thought; what’s the Higgs boson Worth?

That’s a tricky question and one that really doesn’t have an answer, but a man can postulate can’t he!?

In a way there are two answers. On the one hand there’s strict economic amount, measured in real dollars and cold hard Euros. The Large Hadron Collider, the massive particle accelerator buried under Switzerland and France, was built at great expense in part to hunt for the elusive particle. Enormous, house-sized detectors are monitoring trillions of particle collisions looking for signals of the fundamental particle that gives matter its mass. To do this, supercomputers spread out at eleven top tier research institutions across the world are diligently picking apart the terabytes of data produced by the colossal machine.

Dancing Gumby Robot

What do breakdance moves, Gumby and robots have in common? More than you might think: Harvard scientists have created a Gumby-like robot that can do the worm and navigate through tight spaces. You can watch the soft-bodied robot in action below. Pretty awesome!

The robot does the worm under an obstacle. Image courtesy Robert Shepherd/Harvard University via AP.

Inspired by skeleton-less animals like jellyfish, worms and starfish, the team of researchers designed the robot to use compressed air to move its appendages. Equipped with four legs and a core, the robot can perform a variety of movements, ranging from the worm-like movement above to a crawling motion.

Black Friday Crowds: How Physics Can Prevent Tramplings

In the wake of Black Friday's shopping frenzy, several media outlets have reported on shoppers being trampled during the rush for bargains. While this problem rears its head every year, physicists have been researching this area for years. And they have some suggestions for preventing crowd disasters.

A crowd gathers outside a Boise store for Black Friday deals. Image courtesy Robert Barney via Flickr.

To model crowd interactions, physicists often turn to computer simulations of particles. In particular, researchers pored over video evidence of a stampede during a crowded religious pilgrimage that killed over 300 people several years ago. Their research culminated in a highly-cited paper that motivated several changes to the pilgrimage, making it much safer the next year.

Physics of Parade Balloons

Thanksgiving is full of traditions, but few have the same reach as the Macy's Day Parade that reaches 44 million television viewers every year. While bloated balloon animals seem to effortlessly float down New York City Streets, there's actually many hours of preparation required to make sure the parade goes off without a hitch. Below you can find a video detailing the science and "balloonatics" behind the annual event.

An inside look at the Balloonatics behind the annual parade. Video Courtesy Science Friday.

Neutrino Update: New Doubts

Research conducted during the weeks after the recent faster-than-light neutrino observation has contradicted the original finding. When neutrinos travel faster than light, there should be characteristic radiation left in their wake according to new research. Not seeing this radiation in past results from the same beam used in the original experiment, an Italian team from the same laboratory has cast doubt on the existence of superluminal particles.

A neutrino detector buried deep underground in Ontario, CA. Image courtesy A.B. McDonald/The Sudbury Neutrino Observatory Institute.

These results out of Italy represent an analysis of 2010 data through the lens of theoretical research carried out in October. Two researchers at Boston University (BU) published a paper in Physical Review Letters suggesting that neutrino beams should emit radiation in a process analogous to Cherenkov radiation.

Traffic Lasers: Angering Drivers One Ticket at a Time

Affecting about 1 in 6 people every year, traffic tickets can be a source of frustration, financial strain, and roasts by angry bosses when you finally arrive at work. Increasingly, officers are relying on laser technology to catch speeders. But is the Light Detection and Ranging (LIDAR) technology accurate?

Image Courtesy Highway Patrol Images on Flickr.

According to a new report from the U.K.'s Daily Mail newspaper, some LIDAR guns can be wildly inaccurate. An independent expert tested the guns for the newspaper, finding that the guns would sometimes report high speeds for stationary objects and overestimate speeds for bicycles and cars.

World's Lightest Material Unveiled

Scientists have developed the lightest solid ever created—so light that it can rest atop a dandelion without damaging it. The ultra-low density material was inspired in part by lightweight architecture such as the Golden Gate Bridge and the Eiffel Tower.

With an extremely small density, the material can sit atop dandelions. Image Courtesy Dan Little, HRL Laboratories LLC.

Make a Wish: the Leonids are Coming

Look up at the sky tonight, and there's a good chance you'll see a shooting star. Tonight will be the peak of the annual Leonid meteor shower, but it won't be seen in all of its glory due to a bright moon.

A Leonid fireball. Image copyright/credit: Lorenzo Lovato.

Liquid Lakes Form Europa's Blemishes

An artist's rendition of liquid water lakes and a deep, frozen ocean on Jupiter's moon, Europa. New research suggests these bodies of water give rise to "chaotic terrain" on the surface. Image Courtesy Britney Schmidt/Dead Pixel VFX/Univ. of Texas at Austin.

Scientists think they've uncovered a massive liquid water lake just under the surface of Jupiter's moon Europa. While research has already suggested that there is an even larger frozen ocean buried deep beneath Europa, scientists now believe that the ocean is interacting with liquid bodies of water closer to the surface.

Fun Physics Simulations

Have you ever come across a physics phenomenon that you just couldn't wrap your head around? Physics can be tough, but the University of Colorado at Boulder Physics Department has provided a slew of interactive simulations that can help make some of the most difficult concepts a little more understandable.
Click to Run A skate park simulation for learning about conservation of energy. Click above to run the simulation.

Stunning Time Lapse of Earth from Space

Earth | Time Lapse View from Space, Fly Over | NASA, ISS

Above you can see some beautiful time lapse photography of the Earth as taken from the International Space Station. All of the footage was taken between August and October of this year. The video features spectacular views of auroras, sprawling city lights and lightning storms against a Milky Way backdrop. If you click on the link above, you can view the video in HD on Vimeo.

Robojelly, Wine Swirling and Supernovae

What do jellyfish robots, wine glasses and exploding stars have in common? They are all subjects of several novel research projects that will be presented at APS' Annual Meeting for the Division of Fluid Dynamics between November 20 and 22. Held at the Baltimore Convention Center, the meeting is celebrating its 64th year of unveiling exciting physics research. Below is a glimpse at some of the fascinating presentations to be presented at this year's meeting.
Supernova Remnant EO102-72 with X-rays (blue), optical wavelengths (green) and radio (red). Image Courtesy NASA/CXC/SAO

Remote Antarctic Expedition to Reveal Glacial Secrets

13 scientists are traveling to one of Antarctica's most remote areas to examine how warm ocean waters are melting the underbelly of a massive glacier. Conditions are so harsh that the team can only work at their outpost for six weeks before heading back to Mcmurdo Station—Antarctica's science hub.

Glaciologist Robert Bindschadler, the first person to walk on Pine Island Glacier. Image Courtesy NASA

Using satellite measurements, scientists have found that Pine Island Glacier has been rapidly receding into the ocean. Researchers will investigate the area starting in December to determine how quickly the ice is melting and what implications there may be for rising sea levels. Comprising about 10 percent of the West Antarctic Ice Sheet, Pine Island Glacier could contribute significantly to global sea-level rise if it continues to melt.

Spectra Saves Girl's Interest in Science

11 Year Old, Althea, Goes as Laser Super Hero, Spectra, for Halloween
Photo courtesy of Kirsten O'Brien

As Halloween creeps back into the shadows of October one PhysicsCentral reader and comic enthusiast shared her Halloween costume of 2011. This 11 year old from California, didn’t dress up like any regular super hero, no; she went as Spectra, the teenage girl with super hero powers of a laser.

Asteroid Hurtles Past Earth Tonight

At approximately 6:28 EST tonight, a 1,300-foot-wide (400m) asteroid will make its closest pass by Earth. Zooming 201,700 miles (321,867 km) above Earth's surface at its closest approach, asteroid 2005 YU55 will cruise within the moon’s orbit for the entire evening.

Image Courtesy NASA

Luckily for us, the asteroid will fly by without incident. An impact from this asteroid, however, could be devastating. For instance, in 1908, scientists believe that an asteroid or comet detonated above Siberia, demolishing 80 million trees across an area of 2,150 square kilometers (830 square miles). Known as the Tunguska event, the asteroid detonated with an energy equivalent to 10-15 megatons of TNT, 1,000 times more powerful than the atomic bomb dropped on Hiroshima. On top of that, the Tunguska asteroid was likely 4 to 8 times smaller than 2005 YU55.

Frisbee Flight

Hello Physics Buzz readers: As APS’ new science writing intern, I’m excited to join the Physics Buzz blog team. I’m migrating out east from the frigid Rocky Mountains where I studied physics and philosophy at the University of Colorado at Boulder. Before coming to APS, I got my feet wet writing about everything water at the American Water Works Association.My blogger name, Hyperspace, was actually a nickname I picked up during college. I’m an avid ultimate frisbee player, and my quick feet coupled with my physics background gave rise to the name. In honor of one of my favorite pastimes, I’d like to use my first post to give you a crash course on the physics of frisbee flight.

Where Has All the Funny Gone?

There was a weird phenomenon that swept through the 1980s; scientists for half a decade seemed to get really funny. At no point in history have more comedies about scientists been released over such a short time. Science comedies, or sci-coms as I like to think of them, usually track some wacky scientist throwing together some physics-defying invention and having it all go awry, hilariously. It’s a genre that seems to have died, but I guess the flux capacitor that burns twice as bright, burns twice as fast.

Ghostbusters (1984): The granddaddy of them all. Dr. Peter Venkman’s legendary axiom, “Back off man, I’m a scientist,” captures the essence of Ghostbusters, and really sci-coms as a genre. Bringing butt kicking science to paranormal phantasms, Dan Aykroyd, Bill Murray and Harold Ramis are on a mission to rid New York of all pesky ghosts, spirits and other supernatural specters. Technically the team’s made up of parapsychologists, but you have to have a pretty hefty physics backgroun…

Laser Bug Blocker

I hate mosquitoes, and I love physics. That makes this a perfect storm of a story for me.

Want, want, want.

Another Law of Physics Broken?

Just weeks after speeding neutrinos seem to have broken the speed of light, another universal law, the fine structure constant might be about to crumble. Or it might be as concrete and universal as ever, depending on whom you ask.

The laws of physics might change depending on where you are in the universe, claims an Australian team behind a recently published journal article. The paper, appearing in the October 31 issue of Physical Review Letters, asserts that observations of over 300 distant celestial bodies show that the strength of electromagnetism may change at different places in the universe. However this claim has been greeted with much skepticism within the scientific community.

Magic Painting Changes with Heat

There are at least two approaches to creating paper-like computer screens and cell phones that roll up or fold. You could go the route that Samsung is pioneering with smart phones they're making ever more flexible, or you could start with paper and make it smarter.

L.-O. Hennerdal and M. Berggren
Appl. Phys. Lett. 99, 183303 (2011)

Lars-Olov Hennerdal and Magnus Berggren of Linkoping University in Sweden are checking out the second option. They have a long way to go before they will have a piece of paper that acts like a computer display, but they've already made a sheet that can display two different images at the flick of a switch.

A Fermi Halloween

After passing out candy to a group of kids Trick-or-Treating in our office today, and witnessing the shocking burst of hyperactivity the energy-packed sweets produced, we were set to wondering . . . if all the candy passed out to ghouls and goblins at this holiday each year were converted into fuel, how long could it keep the lights on in New York City?

Image by JIP

Is Your House Haunted, Or Are Your Senses Being Taunted?

Supernatural-phenomena skeptics provide scientific explanations and other alternative takes about strange occurrences.

As Halloween approaches, people might find themselves feeling a little spooked. Two individuals identified as "foremost experts of the supernatural realm" have produced a list of phenomena that "might indicate your house is haunted." However, others contend that everything on this list can be perfectly well explained by everyday phenomena.

This photo feature story describes some items from the list, and offers some decidedly non-supernatural explanations from Seth Shostak, SETI Institute senior astronomer and "Big Picture Science" radio host, and from paranormal & pseudoscientific investigator James Randi, founder of the James Randi Educational Foundation.

SENSATION: You see something unexplained out of the corner of your eye.

By TenThirtyNine via flickr | Usage Rights

Truly Scary Stuff

Halloween is coming, and that means it's time to break out the scariest costume you can think of. Zombies, vampires, and Lindsay Lohan are among the most frightening and popular options. Thank goodness none of them are real. But just because the most horrible things we can imagine are make-believe, that doesn't mean that there isn't plenty of real stuff to be afraid of.

Image courtesy of Anthony5429

After several months of collisions at the LHC, even the most nervous people should be able to rest easy that man-made black holes and strange matter particles will not destroy the planet. Still, we at Physics Buzz have the opportunity to talk about plenty of scary things on this blog. Here are some of the topics we've covered in the past that frighten me . . .

1. Creationism

Climate Change is Altering the Lives of Alaska's Natives

Climate change has altered the lives of Native Alaskans in the state's interior in dramatic, sometimes dangerous ways.

Although the effects of change are well documented along the coast, where higher tides and ferocious storms have threatened native communities, a study by the U.S. Geological Survey has found indigenous people in Alaska's interior also have felt the transformation to a warmer climate during the past several decades of their lifetimes.

Superconducting Video

This video has been making the rounds throughout the blogosphere, and with good reason. It's pretty fantastic.

Planet Hunting Through the Rings of Saturn

Planets are formed from when clouds of dust circling a star start to clump together and coalesce into a planet. At the recent Signposts of Planets conference held at the Goddard Space Flight Center, astronomers released the first photo of what is likely a planet forming around a distant star. Because the star is many light years away, the gestating planet only shows up as a smudge in the photograph, so it’s hard to see its finer details, or of its surrounding dust cloud.

In fact over 100 dust clouds have been found circling around far away stars, and many of them likely have planets hiding some were inside them too. Astronomers have been scrutinizing these dust clouds to better understand how planets form inside of them, but it’s hard to get much resolution on these tiny spots of light.

Fortunately though, we have an ideal model right here in our own backyard; Saturn. Really, on the cosmic scale, it’s pretty much in our living rooms.

Blue Steel, Or I Guess Red-Hot, Flaming Steel

Steel is not something that burns, right?In fact, fire doors are often made of steel for that reason.And everyone has seen something rust.Usually something you like, like your car.Rusting is a neat little reaction and it turns out that if it happens fast enough it can actually light steel on fire.And of course, if it is possible to light something on fire, particularly something odd and smelly, we here at Physics Buzz have tried it.

Do White LEDs Disrupt our Biological Clocks?

Chronobiologists and vision scientists are actively investigating the effects of blue-rich light.

You come into contact every day with light-emitting diodes (LEDs) -- they illuminate alarm clocks, new televisions, traffic lights, and smartphone displays. Increasingly, you will see white-light versions of LEDs becoming available for energy-efficient home lighting, car headlights, and streetlamps.

What you may not know is that the most common form of white LEDs -- which emit a spectrum of colors, including blue light -- is inadvertently effective at sending signals to our brain’s biological clock, which regulates daily activities such as sleep.

Fossil Moths Reveal Their True Colors

Moths dead for 47 million years are again showing their true colors. For the first time, scientists have reconstructed the colors of an ancient fossil moth. The findings detailed not just a few spots of color, but the appearance of the entire organism.

[Microscopic structures can create colors in moths and butterflies, as illustrated in this image from a paper published in Physical Review E last year. Vigneron et al., Phys. Rev. E 82, 021903 (2010)]

The Downside of Physics Research

You might think nuclear weapons are the worst thing to come from physics research. Listen to this tune about faster than light neutrinos, and you could change your mind.

Hunting the Higgs? There's an (Android) App for That*

Wanna know how the search for the Higgs is going? Just download the Android app LHSee.

You can get the free app right now by way of the Android Marketplace.

Dark Matters

My first response to Tuesday’s announcement that this year's Nobel Prize would be shared among scientists who measured the acceleration of the universe’s expansion, was surprise. It’s a young discovery, only made in 1998; usually when someone wins a Nobel Prize it’s for work done several decades previously. What was so surprising to me, was that the committee seemed to have leapfrogged over the discovery of dark matter to honor the discovery of dark energy.

In a nutshell, Perlmutter, Schmidt and Riess won for discovering that the universe is accelerating while it’s expanding, totally contrary to expectations that held that because of gravity, the universe’s expansion should be slowing down. No question that this is Nobel Prize worthy research, as it totally shook the foundations of cosmology when it was announced. Soon after the discovery the term “dark energy” was coined, and it was calculated to make up three quarters of the known universe.

But what about this other “dark” stuff t…

2011 Chemistry Nobel for . . . Quasicrystal Physics!

This year's Nobel Prize for Chemistry has roots in physics research from 1984. The following is the story of quasicrystals as told by 2011 Laureate Dan Shechtman to APS News in 2003.

PRL Top Ten: #8

Metallic Phase with Long-Range Orientational Order and No Translational Symmetry
D.Shechtman, I. Blech, D. Gratias, and J.W. Cahn, Phys. Rev. Lett. 53, 1951 (1984), 2155 citations

This is the third in a series of articles by James Riordon. The first article appeared in the November 2003 issue of APS News.

While he was on sabbatical at the National Bureau of Standards in April 1982, Dan Shechtman made a startling discovery. He found that certain rapidly-cooled alloys of aluminum and manganese he was studying produced electron diffraction patterns just as crystals do, but the patterns showed that the alloy had an unusual rotational symmetry. In fact, the symmetry was inconsistent with the patterns that effectively defined a crystal. Shechtman had inadvertently stumbled across a quasicrystal.

Physics Nobel Prize

Three American scientists were awarded the 2011 Nobel Prize for physics for “the discovery of the accelerating expansion of the Universe through observations of distant supernovae.

The Nobel Prize Committee said that half of the award was given to Saul Perlmutter currently at Lawrence Berkeley National Laboratory, while the other half was split between Brian Schmidt at the Australian National University and Adam Riess at Johns Hopkins University.