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This is really cool. I know one of the authors and he is a good guy... the only thing that leaves me unsatisfied is that if the whole issue is related to thermal effects one should have seen the Pioneer effect all the time and not only at about 10 AU... ...or is there some thermal process that kicked in only at this distance?

Here's an update on this theory: NASA Releases New Pioneer Anomaly Analysis "The mysterious force acting on the Pioneer spacecraft seems to be falling exponentially. That's a strong clue that on-board heat is to blame, says NASA." Heat emission 'most likely cause' of pioneer anomaly "What's more interesting is that, contrary to the original analysis conducted all those years ago, the deceleration does seem to be decelerating at an exponential rate -- just as one might expect from the radioactive decay of plutonium-238, which powers the two spacecraft. Turyshev concludes, "The most likely cause of the Pioneer anomaly is the anisotropic emission of on-board heat.""

"The BICEP2 data would eliminate about 90% of inflationary models, Andrei Linde, a cosmologist at Stanford University in California, told a packed auditorium at MIT the day after the BICEP2 announcement (see picture below). Many of those models do not produce gravitational waves at detectable levels, said Linde, who is one of the founders of inflation theory." Is there any hope for LISA now?

Of course - the data is more proof that GWs exist!!

so you don't expect any impact on the science objectives of Lisa at all?

Positioning via accumulated accelerometer data used to stabilize cold trapped atoms. Current systems are not very reliable for submarines, which cannot use GPS underwater. To create the supersensitive quantum accelerometers, Stansfield's team was inspired by the Nobel-prizewinning discovery that lasers can trap and cool a cloud of atoms placed in a vacuum to a fraction of a degree above absolute zero. Once chilled, the atoms achieve a quantum state that is easily perturbed by an outside force - and another laser beam can then be used to track them. This looks out for any changes caused by a perturbation, which are then used to calculate the size of the outside force.

Some bacteria can influence the weather. Up high in the sky where clouds form, water droplets condense and ice crystal grow around tiny particles. Typically these particles are dust, pollen, or even soot from a wildfire. But recently scientists have begun to realize that some of these little particles are alive - they are bacteria evolved to create ice or water droplets around themselves. old but might be worth a discussion

Droplets can be made to chase each other around a track and even self-assemble into devices, simply by mixing two everyday liquids. This remarkable discovery made by scientists in the US has already been used to create beautiful shapes and patterns, and could also be exploited to create optical components that assemble themselves and even to clean surfaces. It looks very like Jojo's self-assembling balls :p

Responding to calls from the National Science Foundation (NSF) and White House Office of Science and Technology Policy (OSTP), a working group of the American Statistical Association has developed a whitepaper detailing how statisticians and computer scientists can contribute to administration research initiatives and priorities. The whitepaper includes a lot of topics central to machine learning and data mining, so please take a look.

I guess Norvig is trumping Chomsky big time if this is the attitude of the NSF :)))

Kip Thorne looks into the black hole he helped create and thinks, "Why, of course. That's what it would do." This particular black hole is a simulation of unprecedented accuracy. It appears to spin at nearly the speed of light, dragging bits of the universe along with it.

From the section Science & Environment Scientists are claiming a stunning discovery in their quest to fully understand gravity. They have observed the warping of space-time generated by the collision of two black holes more than a billion light-years from Earth.

Hundreds of hidden nearby galaxies have been studied for the first time, shedding light on a mysterious gravitational anomaly dubbed the Great Attractor. Despite being just 250 million light years from Earth-very close in astronomical terms-the new galaxies had been hidden from view until now by our own galaxy, the Milky Way. Using CSIRO's Parkes radio telescope equipped with an innovative receiver, an international team of scientists were able to see through the stars and dust of the Milky Way, into a previously unexplored region of space. The discovery may help to explain the Great Attractor region, which appears to be drawing the Milky Way and hundreds of thousands of other galaxies towards it with a gravitational force equivalent to a million billion Suns. Lead author Professor Lister Staveley-Smith, from The University of Western Australia node of the International Centre for Radio Astronomy Research (ICRAR), said the team found 883 galaxies, a third of which had never been seen before. "The Milky Way is very beautiful of course and it's very interesting to study our own galaxy but it completely blocks out the view of the more distant galaxies behind it," he said. Professor Staveley-Smith said scientists have been trying to get to the bottom of the mysterious Great Attractor since major deviations from universal expansion were first discovered in the 1970s and 1980s. "We don't actually understand what's causing this gravitational acceleration on the Milky Way or where it's coming from," he said. "We know that in this region there are a few very large collections of galaxies we call clusters or superclusters, and our whole Milky Way is moving towards them at more than two million kilometres per hour." The research identified several new structures that could help to explain the movement of the Milky Way, including three galaxy concentrations (named NW1, NW2 and NW3) and two new clusters (named CW1 and CW2).

In 1655 the English mathematician John Wallis published a book in which he derived a formula for pi as the product of an infinite series of ratios. Now researchers from the University of Rochester, in a surprise discovery, have found the same formula in quantum mechanical calculations of the energy levels of a hydrogen atom.

This is insanity, Max. Or maybe it's genius.

Protein Folding solved by AI?

"A paper posted online in January takes theoretical computer scientists halfway toward proving one of the biggest conjectures in their field. The new study, when combined with three other recent papers, offers the first tangible progress toward proving the Unique Games Conjecture since it was proposed in 2002 by Subhash Khot, a computer scientist now at New York University. Over the past decade and a half, the conjecture - which asks whether you can efficiently color networks in a certain way - has inspired discoveries in topics as diverse as the geometry of foams and the stability of election systems. And if the conjecture can be proved, its implications will reach far beyond network-coloring: It will establish what is the best algorithm for every problem in which you're trying to satisfy as many as possible of a set of constraints - the rules in a sudoku puzzle, or the seating preferences of a collection of wedding guests, for instance."

go MarsExpress go ... nice results from its radar!