This week, a team of astronomers announced the first “smoking gun” evidence of inflation, a theory of cosmology that describes the quick and violent expansion of the universe in its first fractions of a second. Inflation is the “‘bang’ of the Big Bang,” says Alan Guth, an MIT physics professor who first proposed the theory in 1980. “In its original form, the Big Bang theory never was a theory of the bang. It said nothing about what banged, why it banged, or what happened before it banged.”

The astronomers peered into the cosmic microwave background, a bath of radiation from the early universe, and saw the influence of ripples in space-time, known as gravitational waves. These offer extremely strong evidence that the universe expanded by a repulsive form of gravity, as described by Guth and others.

Explore Professor Guth’s research in the Open Access Articles collection in DSpace@MIT, where it is openly accessible to the world.

Since the MIT faculty established their Open Access Policy in March 2009 they have made thousands of research papers freely available to the world via DSpace@MIT. To highlight that research, we’re offering a series of blog posts that link news stories about scholars’ work to their open access papers in DSpace.