Finding gravity waves may validate 'big bang' theory

Washington, Feb 17 (ANI): Cosmologists are searching the deep reaches of space for the presence of gravity waves, which would give credence to the big bang theory that lead to the beginning of the Universe.

During the next decade, a delicate measurement of primordial light could reveal convincing evidence for the popular cosmic inflation theory, which proposes that a random, microscopic density fluctuation in the fabric of space and time gave birth to the universe in a hot big bang approximately 13.7 billion years ago.

Among the cosmologists searching for these weak signals will be John Carlstrom, the S. Chandrasekhar Distinguished Service Professor in Astronomy and Astrophysics at the University of Chicago.

Carlstrom operates the South Pole Telescope (SPT) with a team of scientists from nine institutions in their search for evidence about the origins and evolution of the universe.

Now on their agenda is putting cosmic inflation theory to its most stringent observational test so far.

The test is detecting extremely weak gravity waves, which Einstein's theory of general relativity predicts that cosmic inflation should produce.

"If you detect gravity waves, it tells you a whole lot about inflation for our universe," Carlstrom said.

It also would rule out various competing ideas for the origin of the universe.

"There are fewer than there used to be, but they don't predict that you have such an extreme, hot big bang, this quantum fluctuation, to start with," said Carlstrom.

Nor would they produce gravity waves at detectable levels.

The phenomenon of cosmic inflation would have produced two classes of perturbations. The first, fluctuations in the density of subatomic particles happen continuously throughout the universe, and scientists have already observed them.

"Usually, they're just taking place on the atomic scale. We never even notice them," said cosmologist Scott Dodelson.

But inflation would instantaneously stretch these perturbations into cosmic proportions.

"That picture actually works. We can calculate what those perturbations should look like, and it turns out they are exactly right to produce the galaxies we see in the universe," said Dodelson.

The second class of perturbations would be gravity waves-Einsteinian distortions in space and time.

Gravity waves also would get promoted to cosmic proportions, perhaps even strong enough for cosmologists to detect them with sensitive telescopes tuned to the proper frequency of electromagnetic radiation.

Carlstrom and his associates are building a special instrument, a polarimeter, as an attachment to the SPT, to search for gravity waves.

The SPT operates at submillimeter wavelengths, between microwaves and the infrared on the electromagnetic spectrum. (ANI)