‘Test tube universe’ hints at unifying theory

Test tubes

A “universe in a test tube” that could be used to assess theories of everything has been created by physicists.

  • Time is running out – literally, say scientists”
  • Are we missing a dimension of time?
  • Are dark forces at work in space?
  • The test tube, the size of a little finger, has been cooled to a fraction of a degree above the lowest possible temperature, absolute zero, which is just over 273 degrees below the freezing point of water.

    Does one of these test tubes hold a baby Universe?

    Inside the tube an isotope of helium (called helium three) forms a “superfluid”, an ordered liquid where all the atoms are in the same state according to the theory that rules the subatomic domain, called quantum theory.

    What is remarkable is that atoms in the liquid, at temperatures within a thousandth of a degree of absolute zero, form structures that, according to the team at Lancaster University, are similar those seen in the cosmos.

    “In effect, we have made a universe in a test tube,” says Richard Haley, who did the work with Prof George Pickett and other members of the “Ultra-low Temperature Group.”

    The Holy Grail of physics is to establish an overarching explanation to unite all the particles and forces of the cosmos. But one of the complaints commonly levelled at a leading contender for a “theory of everything”, called string theory, is that it is impossible to test.

    But now, according to the study in the journal Nature Physics, it may be possible using the universe in a test tube. “It was a serendipitous discovery,” says Haley.

    The equations used to describe this superfluid turn up in many other branches of physics. “For instance, the internal structure of the superfluid mirrors very closely the structure of space-time itself, the ‘background’ of the universe in which we live,” says Haley.

    “Consequently the superfluid can be used to simulate particle and cosmic phenomena; black holes, cosmic strings and the Big Bang for instance.

    “This is great for testing theories, since the equations describing helium-3 are well-established enough to say that it is the most complex system for which we already have the ‘Theory of Everything’,” Haley continues.

    “If the analogous experiments don’t work in helium-3, then it’s probably time to go back to the drawing board (or computer) with your latest pet theory.”

    Since the pioneering work of Albert Einstein, the quest for a theory of everything has depended on combining theories of the very small (quantum theory) and the very large (relativity).

    One of the strangest features of such theories is that they require the universe to have more than three spatial dimensions to unify our picture of all forces and all matter. One promising candidate is supersymmetric string theory, in which ripples on strings are interpreted as particles. But, to their surprise, physicists found five superstring theories. Now the Lancaster experiments provide new insights into the phenomena predicted by these theories.

    For the past three decades it has been known that strings are one member of a bigger class of objects called branes, which exist in higher dimensional space, that could be extended in more than one dimension – from strings of one dimension, to membranes of two dimensions, to those of p dimensions, dubbed p-branes. Moreover string theories and p-branes are facets of one underlying 11-dimensional M theory, which suggests that we live in a brane world: a four-dimensional surface, or brane, in a higher dimensional mixture of space and time.

    People and most particles move in the brane, while the higher dimensions provide a framework to unify all forces, from gravity to those that act between atomic particles. While experiments have begun to highlight cracks in the current best theory, called “the standard model”, there is evidence that M theory’s extra hidden dimensions could be revealed next year when a Geneva atom smasher – the £4.4 billion Large Hadron Collider – begins experiments. But the Lancaster team offers another route to address this impasse.

    One idea is that a collision between a brane and an antibrane could have triggered the Big Bang itself. This can now be simulated in superfluid helium within the little test tube.

     

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    Bush associates still consolidating their hold on US media

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    Longtime associates of President George W. Bush are consolidating their hold on American media with a string of recent purchases.

    Conservative media mogul Rupert Murdoch’s News Corp. announced of late the sale of 8 of its US television stations to a private equity firm — Oak Hill Partners — for an estimated $1.1 billion dollars that is expected to close sometime in 2008.

    The deal leaves Murdoch with another 27 television stations in major US cities such as Boston, New York City, and Los Angeles, as well as The New York Post, a controlling interest in BSkyB, movie studio 20th Century Fox, and Wall Street Journal publisher Dow Jones & Co Inc.

    Oak Hill Partners lead investor Robert M. Bass, a longtime associate of George W. Bush, is also the founder of Ft. Worth, Texas-based Bass Brothers Enterprises. Oak Hill issued a statement announcing the stations would be jointly managed by a broadcast holding company, Local TV, that was created by Oak Hill for the purpose of purchasing 9 other television stations from The New York Times previously this year.

    Conservative ties for the Bass Brothers

    Robert Bass, along with his brothers Lee, Ed, and Sid, from a wealthy Texas oil family, all attended Yale University where Ed was a classmate and friend of George W. Bush. The brothers later became Bush’s number 5 career patrons, as well as business dealings with now President Bush.

    Robert Bass is also the founder and chairman of Aerion Corporation, which has been the recipient of several very lucrative DARPA contracts for the development of supersonic laminar flow wing studies, along with research and test flights.

    News Corp. had originally intended to sell off 9 of its US television stations; however Bass’s subsidiary, Local TV, could not purchase WHBQ-TV in Memphis, Tennessee as it had previously purchased CBS affiliate WREG-TV: “Federal Communications Commission rules allow market duopolies but only one of the two stations under a single owner can be among the market’s four top-rated stations there and there must be least eight unique station owners in the market once the duopoly is formed.”

    Local TV, LLC

    From Local TV, LLC’s homepage:

    “The company will immediately focus on back office and administrative functions,” adds Lawrence. “Then we will move to creating specialized knowledge teams for TV assets, addressing market-specific challenges and opportunities with special swat teams, developing vertical and homegrown content, and finding new ways to deploy capital. And that is just the beginning.”

    The site also lists among its holdings in a statement issued online prior to the News Corps purchase, 23 large and mid-size stations, as well as the 9 small to mid-sized stations purchased from The New York Times.

    Arctic summers ice-free ‘by 2013’

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    Scientists in the US have presented one of the most dramatic forecasts yet for the disappearance of Arctic sea ice.

    Their latest modelling studies indicate northern polar waters could be ice-free in summers within just 5-6 years.

    Professor Wieslaw Maslowski told an American Geophysical Union meeting that previous projections had underestimated the processes now driving ice loss.

    Summer melting this year reduced the ice cover to 4.13 million sq km, the smallest ever extent in modern times.

    Remarkably, this stunning low point was not even incorporated into the model runs of Professor Maslowski and his team, which used data sets from 1979 to 2004 to constrain their future projections.

    In the end, it will just melt away quite suddenly

    Professor Peter Wadhams

    “Our projection of 2013 for the removal of ice in summer is not accounting for the last two minima, in 2005 and 2007,” the researcher from the Naval Postgraduate School, Monterey, California, explained to the BBC.

    “So given that fact, you can argue that may be our projection of 2013 is already too conservative.”

    Real world

    Using supercomputers to crunch through possible future outcomes has become a standard part of climate science in recent years.

    Professor Maslowski’s group, which includes co-workers at Nasa and the Institute of Oceanology, Polish Academy of Sciences (PAS), is well known for producing modelled dates that are in advance of other teams.

    These other teams have variously produced dates for an open summer ocean that, broadly speaking, go out from about 2040 to 2100.

    But the Monterey researcher believes these models have seriously underestimated some key melting processes. In particular, Professor Maslowski is adamant that models need to incorporate more realistic representations of the way warm water is moving into the Arctic basin from the Pacific and Atlantic oceans.

     

    “My claim is that the global climate models underestimate the amount of heat delivered to the sea ice by oceanic advection,” Professor Maslowski said.

    “The reason is that their low spatial resolution actually limits them from seeing important detailed factors.

    “We use a high-resolution regional model for the Arctic Ocean and sea ice forced with realistic atmospheric data. This way, we get much more realistic forcing, from above by the atmosphere and from the bottom by the ocean.”

    The Intergovernmental Panel on Climate Change (IPCC), the UN-led body which assesses the state of the Earth’s climate system, uses an averaged group of models to forecast ice loss in the Arctic.

    But it is has become apparent in recent years that the real, observed rate of summer ice melting is now starting to run well ahead of the models.

    The minimum ice extent reached in September 2007 shattered the previous record for ice withdrawal set in 2005, of 5.32 million square km.

    The long-term average minimum, based on data from 1979 to 2000, is 6.74 million square km. In comparison, 2007 was lower by 2.61 million square km, an area approximately equal to the size of Alaska and Texas combined, or the size of 10 United Kingdoms.

    Diminishing returns

    Professor Peter Wadhams from Cambridge University, UK, is an expert on Arctic ice. He has used sonar data collected by Royal Navy submarines to show that the volume loss is outstripping even area withdrawal, which is in agreement with the model result of Professor Maslowski.

    “Some models have not been taking proper account of the physical processes that go on,” he commented.

    “The ice is thinning faster than it is shrinking; and some modellers have been assuming the ice was a rather thick slab.

    “Wieslaw’s model is more efficient because it works with data and it takes account of processes that happen internally in the ice.”

    Polar bears (Keith Levesque)

    Along the Northwest Passage

    He cited the ice-albedo feedback effect in which open water receives more solar radiation, which in turn leads to additional warming and further melting.

    Professor Wadhams said the Arctic was now being set up for further ice loss in the coming years.

    “The implication is that this is not a cycle, not just a fluctuation. The loss this year will precondition the ice for the same thing to happen again next year, only worse.

    “There will be even more opening up, even more absorption and even more melting.

    “In the end, it will just melt away quite suddenly. It might not be as early as 2013 but it will be soon, much earlier than 2040.”

    The US National Snow and Ice Data Center (NSIDC) collects the observational data on the extent of Arctic sea ice, delivering regular status bulletins. Its research scientist Dr Mark Serreze was asked to give one of the main lectures here at this year’s AGU Fall Meeting.

    Discussing the possibility for an open Arctic ocean in summer months, he told the meeting: “A few years ago, even I was thinking 2050, 2070, out beyond the year 2100, because that’s what our models were telling us. But as we’ve seen, the models aren’t fast enough right now; we are losing ice at a much more rapid rate.

    “My thinking on this is that 2030 is not an unreasonable date to be thinking of.”

    And later, to the BBC, Dr Serreze added: “I think Wieslaw is probably a little aggressive in his projections, simply because the luck of the draw means natural variability can kick in to give you a few years in which the ice loss is a little less than you’ve had in previous years. But Wieslaw is a smart guy and it would not surprise me if his projections came out.”

    Former US Vice President Al Gore cited Professor Maslowski’s analysis on Monday in his acceptance speech at the Nobel Peace Prize ceremony in Oslo.