PITTSBURGH—At a meeting of the American Physical Society (APS) here this past week, physical chemist W. E. Moerner of Stanford University presented a clever new trick for looking inside living cells. The technique allows views in three-dimensions and well beyond the so-called diffraction limit that ordinarily fuzzes up images at around half the wavelength of the light used. Moerner was this year's recipient of the APS's Irving Langmuir Prize in Physical Chemistry.

Techniques such as electron microscopy have long allowed exquisite imaging at the nanoscale, but they typically require careful preparation of the object to be imaged and are not practical for, say, looking inside living cells to see the processes taking place there. As physics students learn early on in optics, the best images usually obtainable using light can make out features no smaller than about half the light's wavelength, or about 200 nanometers using the shortest-wavelength visible light. (A nanometer is a billionth of a meter, or about 40 billionths of an inch.) Biochemical structures in cells are much smaller than that.

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PITTSBURGH—Look in that lab: it's a gas, it's a solid, it's a superfluid—it's SuperSolid! Well, maybe.

The "it" in question is a collection of rubidium atoms cooled to within a whisker of absolute zero and the lab is physicist Dan Stamper-Kurn's at the University of California, Berkeley. His group is working on clouds of the ultracold atoms that exhibit properties of multiple states of matter at once. Stamper-Kurn announced the details of the research yesterday at the American Physical Society meeting here.

Ultracold rubidium has achieved fame before, being one of the gases first turned into a Bose-Einstein condensate in the mid-1990s (at that time Stamper-Kurn was a graduate student in 2001 Nobelist Wolfgang Ketterle's group at the Massachusetts Institute of Technology, but that is another story, involving rubidium's cousin sodium).

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Earlier this week, the Templeton Foundation announced the 2009 winner of its $1.4 million Templeton Prize, French physicist and philosopher Bernard d’Espagnat. He is best known for his work to understand and test one of the strangest predictions of the theory of quantum mechanics: that particles are uncannily good players of The Newlywed Game. Pairs of them can give exactly the same responses to measurements conducted on them at the same time in isolated booths.

In the 1960s, physicist John Stewart Bell derived a set of mathematical inequalities that the responses would obey if the particles had some kind of a built-in cheat sheet. But d’Espagnat, Alain Aspect, and other experimenters found that particles violate these inequalities. Somehow the particles retain an intimate connection that transcends space. Physicists, even the most romantically inclined among them, have yet to fathom it.

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As the call for a clean-energy savior—to wash away our fossil-fuel sins—grows louder, the number of questionable candidates swells. Should we be looking to photovoltaic or fusion? Turbines or tides? With thanks to readers who responded to our Twitter call for favorite alt-energy duds, here's a roundup of five ideas that may one day succeed, but aren't going to save the globe from a climate calamity anytime soon.

Zero-point energy
Some have posited that looking to the very small – as in quantum – might help solve the very big global energy need.  According to quantum mechanics, a perfect vacuum actually contains a bit of energy, which can create particles that pop into existence out of nowhere before quickly disappearing again. Physicists have seen this zero-point energy in the form of the Casimir effect in which two closely spaced plates in a vacuum are pushed together ever so slightly by this energy. But one of the big problems would be capturing useful amounts of energy; after all, it takes at least as much energy to pull the plates apart again. Nevertheless, plenty of so-called "perpetual motion" devices using zero-point energy have been proposed, but careful analysis inevitably shows that such schemes violate at least one law of thermodynamics, and nothing concrete (or even too theoretically plausible) has materialized just yet.

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Astronauts aboard the International Space Station (ISS) may have to maneuver the station to evade flying junk as the space shuttle Discovery closes in for docking. The warning comes just four days after the crew was forced to take refuge in an escape capsule as a last-minute risk of debris strike was discovered.

Like last week's chunk of debris, which passed without incident as the three ISS members huddled in the station's Soyuz capsule, tomorrow's threatening object is not related to last month's collision between a Russian satellite and a commercial communications satellite.

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A new study says that the average American is exposed to six times more radiation from medical tests than in the early 1980s, prompting warnings that physicians may be upping patients' cancer risk by giving them unnecessary exams. 

A study by The National Council of Radiation Protection and Measurements (NCRP) shows that the average American's overall radiation exposure jumped from 3.6 millisieverts (mSv) to 6.2 mSv per year -- almost entirely a result of radiation-based medical tests. These tests, once responsible for only 15 percent of Americans' exposure to radiation, now account for nearly 50 percent. In contrast, there was almost no change in so-called background radiation, which naturally emanates from soil, rocks and other environmental substances.

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Black holes, as frighteningly extreme as they may be, are relatively commonplace across the universe. Like most large galaxies, our own Milky Way packs a supermassive black hole at its core, a lurking monster some four million times as massive as the sun.

But our own neighborhood bully appears relatively tame next to a distant quasar, or bright galactic center, recently spotted by astronomers Todd Boroson and Tod Lauer of the National Optical Astronomy Observatory (NOAO) in Tucson, Ariz. The quasar, known as SDSS J153636.22+044127.0, appears to host a pair of black holes, bound together in a tight orbital relationship, circling each other every 100 or so years. The finding appears today in Nature.

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Saturn's G ring, a faint band of material near the outer bounds of the planet's famed ring system, hosts a bright arc about 90,000 miles (150,000 kilometers) long. The arc, or partial ring, which stretches through about a sixth of the G ring's length, is believed to provide the rest of the ring with dust and ice, but its evolution has remained a mystery.

Recent images from the Cassini spacecraft (at left) point to a moonlet embedded in the G ring. The moonlet, the Cassini team speculates, might help to repopulate the arc, and then the ring as a whole, with material as it suffers collisions with meteoroids or other small bodies within the ring.

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Ice cores drilled from the poles have provided valuable historical climate records, as the composition of the ice and the air bubbles trapped therein offers a relatively pristine glimpse of ancient conditions. Now a group of Japanese scientists says that the same technique may yield records of significant astronomical events as well.

In a paper posted recently to arxiv.org, Yuko Motizuki of the RIKEN Nishina Center for Accelerator-Based Science in Wako, Japan, and colleagues present evidence for an Antarctic ice-core record of supernovae, or stellar explosions, a millennium ago. A 400-foot (122-meter) core pulled up in 2001 at Dome Fuji station in East Antarctica shows spikes in the concentration of nitrate ion (NO₃^–) that coincide with two known supernovae in the 11th century: supernova 1006, named for the year it was observed, and the Crab Nebula supernova of 1054. (Astronomers and astrologers in the Far East and the Middle East were already making detailed records of such events by that time.) Nearby supernovae, the researchers write, shower Earth with gamma rays, which can boost levels of nitrogen oxides in the atmosphere that might be recorded as nitrate spikes in the ice.

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Nearly a decade ago, Leik Myrabo shared with Scientific American readers his vision for the future of space travel: a "LightCraft" pushed out to the stars by a pulsed infrared laser beam from the ground or pulled into space by a laser beamed down from a solar-powered station orbiting Earth. (Read the article here.) Myrabo, an associate professor of engineering physics at Rensselaer Polytechnic Institute in Troy, N.Y., described in his April 1999 article a grand plan for constructing these orbital stations and a beamed-energy craft that could transport passengers out to space.

Ten years—and reportedly 140 test flights using small prototypes—later, he foresees laser flight carrying people around the globe and into space by 2020, Wired.com reported from "Expanding the Vision of Sustainable Mobility," a conference hosted last week by the Art Center College of Design in Pasadena, Calif. For this scenario, ground-based lasers called LightPorts would provide the energy needed to propel the crafts, although Myrabo acknowledges that this won't become viable until more powerful lasers are developed and jet fuel becomes expensive enough to force the aviation industry to search for an alternative.

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