In the beginning, the universe got very big very fast, transforming itself in a fraction of an instant from something almost infinitesimally small to something imponderably vast, a cosmos so huge that no one will ever be able to see it all.

This is the premise of an idea called cosmic inflation — a powerful twist on the big-bang theory — and Monday it received a major boost from an experiment at the South Pole called BICEP2. A team of astronomers led by John Kovac of the Harvard-Smithsonian Center for Astrophysics announced that it had detected ripples from gravitational waves created in a violent inflationary event at the dawn of time.“We’re very excited to present our results because they seem to match the prediction of the theory so closely,” Kovac said in an interview. “But it’s the case that science can never actually prove a theory to be true. There could always be an alternative explanation that we haven’t been clever enough to think of.”

The reaction in the scientific community was cautiously exultant. The new result was hailed as potentially one of the biggest discoveries of the past two decades.

There was nothing, and then, in an instant, there was something. It’s almost like somebody created the cosmos out of nothing.