Key Discovery Related to Big Bang Theory Unveiled: Evidence of Cosmic Inflation

Key Discovery Related to Big Bang Theory Unveiled: Evidence of Cosmic Inflation
Conceptual diagram of what may have happened from the time of the Big Bang, more than 13 billion years ago, to today. NASA/WMAP Science Team
Tara MacIsaac
Updated:

A team at the Harvard-Smithsonian Center for Astrophysics announced Monday that it has found evidence of the rapid expansion of matter in the very first moments following the Big Bang, about 14 billion years ago.

It is being hailed as a landmark discovery that could lead to a Nobel Prize if confirmed through peer review.

The theory of cosmic inflation holds that the matter in the universe expanded exponentially after the Big Bang—in the first trillionth of a trillionth of a trillionth of a second, the universe went from a billionth the size of a proton to about the size of a marble, and it’s been expanding ever since.

Though this theory has had wide support among astrophysicists, it has been difficult to find proof. The idea is that, if such an inflation occurred, the evidence would be left in the form of ripples imprinted on the Cosmic Microwave Background (a kind of radiation we can observe in the cosmos, which is believed to have been produced by the Big Bang and which is studied to understand how the known universe developed). 

It is exactly this imprint that the team says it has discovered. The team’s data also show the first images of gravitational waves, or ripples in space-time. These waves were predicted in Albert Einstein’s theory of relativity, but they have never been observed until now. 

John Kovac, associate professor of astronomy at the Harvard-Smithsonian Center for Astrophysics who led the team, said in a statement,“Detecting this signal is one of the most important goals in cosmology today.” 

In 1922, Alexander Alexandrovich Friedmann provided the calculations on which the Big Bang theory was founded. In 1979, Alan Harvey Guth proposed the theory of exponential expansion. Guth said the cosmic inflation was the “bang” in the Big Bang. This new discovery could be the next big step in understanding the origins of the known universe. 


Ripples in space-time observed by the Bicep2 telescope at the South Pole. The ripples are believed to be evidence of the exponential expansion of our universe in the first fractions of a second after the Big Bang. (Courtesy of Harvard-Smithsonian Center for Astrophysics)