By Ron Cowen
The most detailed portrait ever taken of the radiation left over from the Big Bang provides fresh evidence that the universe began with a tremendous growth spurt, expanding from subatomic scales to the size of a grapefruit in less than a trillionth of a second.
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In that instant, according to the theory known as inflation, microscopic fluctuations in the density of the cosmos were greatly amplified. That blueprint ultimately developed into the rich tapestry of stars and galaxies that fill the universe today. Although inflation has explained a multitude of features about the universe, before the new evidence, many details had yet to be scrutinized.