Creation of a miniature universe yields snapshot of the Big Bang The image at left shows the density of atoms at the beginning of an experiment simulating the evolution of the universe following the big bang. The predominance of red indicates the higher central density of ultracold atoms. The red cloud of atoms measures approximately 10 microns by 10 microns - smaller than the diameter of a human hair. Eighty milliseconds after the simulated big bang, the atoms have become much less concentrated in the experimental vacuum chamber, as indicated (at right) by the color gradation from red to yellow, green, blue and purple in the density map. Credit: University of Chicago CHICAGO, Aug. 30 (UPI) -- U.S. physicists say they've simulated the radiation created by the Big Bang in a laboratory to better understand how structure evolved in the infant universe. Using ultra-cold cesium atoms in a vacuum chamber at the University of Chicago they reproduced a pattern resembling the cosmic microwave background radiation that is the echo of the birth of the universe, a university release reported. "This is the first time an experiment like this has simulated the evolution of structure in the early universe," physics Professor Cheng Chin said. 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, said researcher Chen-Lung, now at the California Institute of Technology. One can think of the big bang, in oversimplified terms, as an explosion that generated sound, Chin said, in waves that began interfering with each other, creating complicated patterns or oscillations. "That's the origin of complexity we see in the universe," he said. Chin's team chilled a flat, smooth cloud of 10,000 or so cesium atoms to a billionth of a degree above absolute zero, and found they could generate oscillation similar to that created by the Big Bang, creating a kind of snapshot of how the universe appeared at a moment in time long ago. The cesium atom "universe" simulated in the laboratory measured no more than 70 microns in diameter, approximately the diameter of a human hair, Chin said. "It turns out the same kind of physics can happen on vastly different length scales," he explained. That's the power of physics.