What happened before the Big Bang

Washington, Dec 17 (ANI): A team of astrophysicists at the California Institute of Technology (Caltech) has said that their new theoretical interpretation of an imprint from the earliest stages of the universe may also shed light on what came before the Big Bang.

"It's no longer completely crazy to ask what happened before the Big Bang," said Marc Kamionkowski, Caltech's Robinson Professor of Theoretical Physics and Astrophysics.

Kamionkowski joined graduate student Adrienne Erickcek and senior research associate in physics Sean Carroll to propose a mathematical model explaining an anomaly in what is supposed to be a universe of uniformly distributed radiation and matter.

Their investigations turn on a phenomenon called inflation, first proposed in 1980, which posits that space expanded exponentially in the instant following the Big Bang. Inflation starts the universe with a blank slate," Erickcek described.

The hiccup in inflation, however, is that the universe is not as uniform as the simplest form of the theory predicts it to be. Some parts of it are more intensely varied than others.

Until recently, measurements of the Cosmic Microwave Background (CMB) radiation, a form of electromagnetic radiation that permeated the universe 400,000 years after the Big Bang, were consistent with inflation.

Miniscule fluctuations in the CMB seemed to be the same everywhere.

But a few years ago, some researchers scrutinized data from NASA's Wilkinson Microwave Anisotropy Probe (WMAP). They discovered that the amplitude of fluctuations in the CMB is not the same in all directions.

"If your eyes measured radio frequency, you'd see the entire sky glowing. This is what WMAP sees," Kamionkowksi described.

WMAP depicts the CMB as an afterglow of light from shortly after the Big Bang that has decayed to microwave radiation as the universe expanded over the past 13.7 billion years.

Kamionkowksi's model predicts more cold than hot spots in the CMB.

For Erickcek, the team's findings hold the key to understanding more about inflation.

"Inflation is a description of how the universe expanded," she said. "Its predictions have been verified, but what drove it and how long did it last? This is a way to look at what happened during inflation, which has a lot of blanks waiting to be filled in," she added.

But, the perturbation that the researchers introduced may also offer the first glimpse at what came before the Big Bang, because it could be an imprint inherited from the time before inflation.

"All of that stuff is hidden by a veil, observationally," Kamionkowski said. "If our model holds up, we may have a chance to see beyond this veil," she added. (ANI)