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At the time of the big bang, our universe may not have had exactly three dimensions of space and one of time, according to some theorists. In the 6 August Physical Review Letters, a team proposes a way to observe the postulated transition to our current universe using so-called metamaterials, structures in which the propagation of light can be precisely controlled. Experiments on such structures, they say, could test predictions that a "big flash" of radiation would accompany changes in the structure of spacetime that may have occurred in the early universe.

Swarms of insects or schools of fish can suddenly switch direction, seemingly at random. A research team now believes they understand why. In the August Physical Review E they describe experiments with locusts and their mathematical model of the swarm. The model suggests that tiny alignment errors between neighboring individual locusts within the swarm, which normally cancel each other, can accumulate over long times and eventually cause the entire swarm to suddenly move in a new direction.

A radar experiment aboard India's Chandrayaan-1 lunar spacecraft has identified thick deposits of water-ice near the Moon's north pole.

The Orbit Determination Program (ODP) of NASA's Jet Propulsion Laboratory, which was used in the data analysis, is based on an expression for the gravitational delay which differs from the standard formula; this difference is of second order in powers of $m$ -- the sun's gravitational radius -- but in Cassini's case it was much larger than the expected order of magnitude $m^2/b$, where $b$ is the ray's closest approach distance. Since the ODP does not account for any other second-order terms, it is necessary, also in view of future more accurate experiments, to systematically evaluate higher order corrections and to determine which terms are significant.

Physicists in France have come up with a new way of using bouncing ultracold atoms to measure the acceleration due to gravity. The technique involves firing vertical laser pulses at a collection of free-falling atoms, which bounces some atoms higher than others. When the atoms recombine at the centre of the experiment, they create an interference pattern that reveals that g is 9.809 m/s2 – just as expected for their Paris lab.

Kilometre-long pulses of light have been stored for over one second in a 0.1 mm cloud of ultracold atoms – before being revived and sent on their way. This latest demonstration of light storage using electromagnetically induced transparency (EIT) is the first to break the second barrier – using ultracold atoms and has the added bonus of preserving the quantum state of the incoming pulse. The physicists in the US who carried out the experiment say that the work could play a key role in quantum information technology.

the discovery will open up a new field of research, and it could lead to a new generation of superefficient light-sensitive devices.

the experiments showed that the electron vibrations resulting from the photons striking the antennas persisted at full strength four times longer than expected. The reason, the researchers report this week in Nature, is that quantum mechanics controls the energy. "It was an utter surprise," says physical chemist and co-author Gregory Scholes of the University of Toronto in Canada. For the results to have occurred, he explains, a property called quantum coherence must have been operating.

the research "will open an entirely new area of biophysics." And that effort should have "huge implications," he says, "not only for how we think about biophysics, but also light harvesting and light-sensitive devices."

Treutlein and colleague’s work represents an important step forward in the use of ultracold atoms to study mechanical systems. "This experiment clearly demonstrates the possibility to use ultracold atomic systems as diagnostic tools and high-precision sensors, this is a very promising route of research," he said.

On Monday the XENON100 collaboration published an analysis of the first experimental results from its dark-matter detector. It reported no evidence of dark matter, the substance thought to constitute over 80% of mass in the universe. The experiment covered a similar parameter range as dark-matter searches DAMA and CoGeNT, which have previously claimed possible evidence for dark matter. As a result, the XENON100 team concluded that both the DAMA and CoGeNT evidence could be excluded. But now the DAMA and CoGeNT collaborations claim that the XENON100 researchers' analysis is flawed, and that their original evidence for dark matter should remain intact

For 15 years, J. Craig Venter has chased a dream: to build a genome from scratch and use it to make synthetic life. Now, he and his team at the J. Craig Venter Institute (JCVI) in Rockville, Maryland, and San Diego, California, say they have realized that dream.

"One thing is sure," Boeke says. "Interesting creatures will be bubbling out of the Venter Institute's labs."