APS Weekly NewsBrief
March 2, 2010

Quantum measurement precision approaches Heisenberg limit
Theoretically, measurement precision is limited by Heisenberg's uncertainty principle. Reaching the Heisenberg limit has generally been a technical impossibility, but physicists are now getting close. Read the associated Physical Review Letters article here.More

Sound lasers inch closer to reality
Fifty years after the invention of the optical laser, two separate research groups have independently made important steps toward making phonon lasers -- a type of laser that emits very high-frequency, coordinated sound rather than light waves -- a reality. The studies, published in the current issue of the journal Physical Review Letters, could lead to a completely new kind of laser that could find interesting applications in medical imaging. Read the associated Viewpoint in APS Physics here.More

Both answers correct in century-old optics dilemma
For 100 years physicists have been struggling to reconcile two different formulations describing the momentum of light traveling through a transparent medium. One, put forward by German mathematician Hermann Minkowski in 1908, stipulates that light's momentum increases when it enters a medium, while the other, advanced a year later by the German physicist Max Abraham, instead says that the momentum of light decreases. Read the associated Physical Review Letters article here.More

Host star caught sucking the atmosphere off a hot Jupiter
Ars Technica
Although gas giants like Jupiter are incredibly massive, the residual heat from their gravitational collapse helps keep the atmosphere in a relatively low-density, gaseous state. A hotter gas giant would have even lower density, and a correspondingly higher radius, which is exactly what we've seen in a number of exoplanets that orbit close to their host stars. Now, researchers have spotted one that's so close and so hot that its host star has distorted its atmosphere into the shape of an American football and is gradually sucking it off the planet. More

Physicists looking to shed more light on dark matter
Los Angeles Times
British and Japanese scientists at the multinational T2K particle-physics project in Japan said Friday that they have observed the experiment's first neutrino to travel 185 miles underground across the Asian country, indicating that the project is now ready to begin doing physics.More

Hogan's noise
The Grinch detested the noise created by the tiny residents of Whoville. Cosmologist Craig Hogan, in contrast, has become enamored of a noise he claims is generated by something even tinier -- a minuscule graininess in the otherwise smooth structure of spacetime. Call it Hogan's noise. Read the associated papers in Physical Review D here and here.

Chip of tooth tells radiation dose
A tiny chip of tooth enamel can tell the tale of radiation exposure, scientists report February 16 at a meeting of the American Physical Society. The technique may allow researchers to better understand the links between radiation exposure and illnesses such as cancer. Knowing normal levels of radiation exposure is important in the event of acute exposures, such as the detonation of a radioactive bomb or nuclear power plant accidents. Click here to read the paper presented at the APS Annual Meeting in Washington, DC.More

Elusive dark matter may be hidden on Earth
Scientists are hot on the tail of one of nature's most elusive substances, the mysterious dark matter that is thought to make up the bulk of the universe. Many scientists think dark matter might even be hiding right under our noses here on Earth.More

It's a golden year for lasers
Fifty years after the first laser was demonstrated, scientists and engineers are celebrating the golden anniversary, marveling over how a once-feared "death ray" now touches almost every aspect of our lives, and setting the stage for future breakthroughs.More

Chilean quake likely shifted Earth's axis, NASA scientist says
The earthquake that killed more than 700 people in Chile on Feb. 27 probably shifted the Earth's axis and shortened the day, a National Aeronautics and Space Administration scientist said.More

Do TV and movies get science right?
Television shows and movies may take you to worlds far away, but their makers, aware of viewers' need for believability, say they consult scientists to make things more real. "Audiences now demand that, or they hunger for it," Academy-Award winning director and producer Ron Howard said at this weekend's meeting of the American Association for the Advancement of Science. "They want it to ring true whenever possible."More

Best science on TV: Comedy Central's Stewart, Colbert?
USA Today
Looking for science? Headed for Animal Planet or the Science Channel? Think again, scientists say: All the cool kids want to sit across from Comedy Central's Jon Stewart and Stephen Colbert.More