News in Science

Meaning of life changes across cosmos

New research suggests the laws of physics aren't the same in all parts of the Universe.

Australian scientists have detected a spatial variation in the fine structure constant, one of the fundamental forces of nature that binds electrons to the nuclei of the atom.

If correct, the discovery could mean only our part of the Universe may be capable of supporting life.

Reporting in the physics blog ArXiv.com, Professor John Webb and PHD student Julian King from the University of New South Wales, describe a change the value of the fine structure constant depending on where you look.

Webb wanted to determine if the fundamental constants of nature might alter in different parts of the universe.

"If the fine structure constant were different elsewhere in the universe, we ought to be able to see the evidence in the way distant gas clouds absorb light on its way here from even more distant quasars," says Webb.

Studies of absorption spectra carried out with the 10 metre Keck telescope in Hawaii, indicate the fine structure constant seems to get slightly smaller the further away you go.

But now, new evidence by Webb and King using the Very Large Telescope (VLT) in Chile, indicates the opposite, that the fine structure constant was slightly larger.

Webb says that's significant because Keck looks out into the northern hemisphere, while the VLT looks south.

"This means in one direction, the fine structure constant was once smaller and in exactly the opposite direction, it was once bigger. And here we are in the middle, where the constant is about 1/137."

Webb's team took 295 measurement of light from distant quasars, all around 12 billion light years away.

"That's a significant percentage of the overall visible universe".

Dipole universe

If correct, the theory fits a dipole model for the universe.

"There seems to be an axis through the cosmos. In one direction, the universe seems to be getting bigger, while in the opposite direction it's getting smaller, not by very much, but it seems to do so significantly."

"What the exact interpretation of that means remains unclear, it's going to require a lot of new physics and there are implications for the other forces of nature as well."

"It also puts a new slant on the question of why the laws of physics seem to be so fine-tuned for life. It could be that it's only fine-tuned in this corner of the universe."