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12175Evolution of Early Universe from Big Bang Simulated in 10 Milliseconds

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  • derhexerus
    Aug 29, 2013
    • 0 Attachment
      URL to an interesting article about the early centuries following the Big
      Bang
      http://tinyurl.com/pqyesll

      Chris

      (I reject your reality and substitute my own)

      First few paragraphs
      "It took the whole universe about 380,000 years to evolve from the Big Bang
      into the cosmic microwave background radiation spectrum, but physicists
      were able to reproduce much the same pattern in approximately 10 milliseconds
      in a new simulation using ultracold cesium atoms in a vacuum chamber at
      the University of Chicago. Their goal is to better understand the cosmic
      evolution of a baby universe, the one that existed shortly after the Big Bang.
      It was much smaller then than it is today, having reached a diameter of
      only a hundred thousand light years by the time it had left the _CMB_
      (http://en.wikipedia.org/wiki/Cosmic_microwave_background_radiation) pattern that
      cosmologists observe on the sky today.“This is the first time an experiment
      like this has simulated the evolution of structure in the early universe,”
      said Cheng Chin, professor in physics. Chin pursued the project with lead
      author Chen-Lung Hung, PhD’11, now at the _California Institute of
      Technology_
      (http://maps.google.com/maps?ll=34.138577,-118.125494&spn=0.01,0.01&q=34.138577,-118.125494 (California%20Institute%20of%20Technology)&t=h) , and
      Victor Gurarie of the _University of Colorado, Boulder_
      (http://maps.google.com/maps?ll=40.0066666667,-105.267222222&spn=0.01,0.01&q=40.0066666667,-105.267
      222222 (University%20of%20Colorado%20at%20Boulder)&t=h) . Their goal was
      to harness ultracold atoms for simulations of the Big Bang to better
      understand how structure evolved in the infant universe.
      The cosmic microwave background is the echo of the Big Bang. Extensive
      measurements of the CMB have come from the orbiting _Cosmic Background
      Explorer_ (http://lambda.gsfc.nasa.gov/product/cobe/) in the 1990s, and later by
      the _Wilkinson Microwave Anisotropy Probe_ (http://map.gsfc.nasa.gov/) and
      various ground-based observatories, including the _UChicago_
      (http://maps.google.com/maps?ll=41.7897222222,-87.5997222222&spn=0.01,0.01&q=41.7897222222,-8
      7.5997222222 (University%20of%20Chicago)&t=h) -led South Pole Telescope
      collaboration. These tools have provided cosmologists with a snapshot of how
      the universe appeared approximately 380,000 years following the Big Bang,
      which marked the beginning of our universe.
      It turns out that under certain conditions, a cloud of atoms chilled to a
      billionth of a degree above absolute zero (-459.67 degrees Fahrenheit) in a
      vacuum chamber displays phenomena similar to those that unfolded following
      the Big Bang, Hung said.
      “At this ultracold temperature, atoms get excited collectively. They act as
      if they are sound waves in air,” he said. The dense package of matter and
      radiation that existed in the very early universe generated similar
      sound-wave excitations, as revealed by COBE, WMAP and the other experiments.
      The synchronized generation of sound waves correlates with cosmologists’
      speculations about inflation in the early universe. “Inflation set out the
      initial conditions for the early universe to create similar sound waves in
      the cosmic fluid formed by matter and radiation,” Hung said.
      The sudden expansion of the universe during its inflationary period created
      ripples in space-time in the echo of the Big Bang. One can think of the
      Big Bang, in oversimplified terms, as an explosion that generated sound, Chin
      said. The sound waves began interfering with each other, creating
      complicated patterns. “That’s the origin of complexity we see in the universe,” he
      said.
      These excitations are called Sakharov acoustic oscillations, named for
      Russian physicist _Andrei Sakharov_
      (http://en.wikipedia.org/wiki/Andrei_Sakharov) , who described the phenomenon in the 1960s. To produce Sakharov
      oscillations, Chin’s team chilled a flat, smooth cloud of 10,000 or so cesium
      atoms to a billionth of a degree above absolute zero, creating an exotic state
      of matter known as a two-dimensional atomic superfluid.
      Then they initiated a quenching process that controlled the strength of the
      interaction between the atoms of the cloud. They found that by suddenly
      making the interactions weaker or stronger, they could generate Sakharov
      oscillations.
      The universe simulated in Chin’s laboratory measured no more than 70
      microns in diameter, approximately the diameter as a human hair. “It turns out
      the same kind of physics can happen on vastly different length scales,” Chin
      explained. “That’s the power of physics.”


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