the physics arXiv blog

Month: October 2008

  • The terrible truth about economics

    “Compared to physics, it seems fair to say that the quantitative success of the economic sciences is disappointing,” begins Jean-Philippe Bouchaud,  an econophysicist at Capital Fund  Management in Paris. That’s something of an understatement given the current global financial crisis. Economic sciences have a poor record of success, partly because they are hard (Newton once…

  • Why PAMELA may not have found dark matter

    This is the one we’ve been waiting for. For months, the astrophysical world has been abuzz with rumors that the orbiting observatory PAMELA has found evidence of dark matter. Various people have speculated on the nature of this dark matter but the PAMELA team has been cautious, refusing to release the data until they are…

  • Why ant colonies don’t have traffic jams

    Traffic jams are the bane of modern life. But could it be possible that one of this planet’s more ancient life forms could show us how to better regulate road traffic? That’s the claim of congestion expert Dirk Helbing at the Dresden University of Technology in Germany and pals using a remarkable insight gained from…

  • Martian methane and the smoking gun of life

    The presence of methane in the Martian atmosphere is a puzzle. Methane is broken down rapidly by sunlight and cannot last long in any atmosphere. A few simple calculations show that the lifetime of a CH4 molecule in martian climes is around 500 years. So methane ought not to exist in the Martian atmosphere at…

  • Slime Mould intelligence points to a new model of AI

    Earlier this year, a group of Japanese scientists reported that with appropriate training, the true slime mold Physarum polycephalum can anticipate the timing of periodic events. That’s more than some politicians can manage and P polycephalum is only a single-celled amoeba, albeit a talented one. A few years ago a Hungarian team showed that slime…

  • Beacons ‘n’ torches

    The best of the rest from the physics arXiv: Rapid Sequencing of Individual DNA Molecules in Graphene Nanogaps Proving Inflation: A Bootstrap Approach The Straw Man of Quantum Physics Quantum Big Bounce Star Formation in the Multiverse

  • Why SETI will have missed any cost conscious ET civilizations

    If we want to contact any of those other civilizations out there, we’ll need a beacon to send messages with. But what to build? Gregory Benford at the University of California Irvine and family (?) have done a cost/benefit analysis on the types of microwave generators out there that can produce the 10^17 W necessary…

  • Frustration with fluid dynamics

    There is no shortage of fascinating videos for the Gallery of Fluid Motion at the upcoming meeting of the American Physical Society Fluid Dynamics division. At least they sound interesting. We’ll never know because they’re practically impossible to download from eCommons library at Cornell University. That’s not good enough. Surely YouTube (or one of its…

  • Here come the quantum robots

    Quantum robots were first investigated in the late 1990s by Paul Benioff, a remarkably original thinker at Argonne National Laboratory in Illinois. Benioff is currently occupied in holding a candle for a theory of everything based on quantum numbers (more or less single handedly). So a team of Chinese physicists led by Daoyi Dong at…

  • How leaves curl up in strong winds

    Various types of plants, fungi and even animals are known to change their shape in strong winds to reduce drag. Leaves, in particular are known to curl up in strong winds. How they do this is not well understood, because of the dynamic nature of the problem and the difficulty taking good data. So Laura…