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Astronomy

Cosmic Inflation and Its Observational Tests

Quick fact

Inflation is theorized to have expanded the universe by at least a factor of 10^26 in less than 10^-32 seconds, faster than the speed of light.

Why this is interesting

You've probably heard of the Big Bang—but what happened in the first fraction of a second? A bizarre idea called inflation suggests the universe expanded faster than the speed of light. How do we know that's true?