Monday, March 17, 2014

BICEP2 Post Big Bang Discovery: Evidence spotted for universe's early expansion

In this 2007 photo provided by Steffen Richter, the sun sets behind the BICEP2 telescope, foreground, and the South Pole Telescope in Antarctica

In the faint glowing remains of the Big Bang, scientists found "smoking gun" evidence that the universe began with a split-second of astonishingly rapid growth from a seed far smaller than an atom. 

To find a pattern of polarization in the faint light left over from the Big Bang, astronomers scanned about 2 percent of the sky for three years with the BICEP2 at the south pole, chosen for its very dry air to aid in the observations, said the leader of the collaboration, John Kovac of Harvard. 

Credit: AP Photo/Steffen Richter

The universe was born almost 14 billion years ago, exploding into existence in an event called the Big Bang.

Now researchers say they've spotted evidence that a split-second later, the expansion of the cosmos began with a powerful jump-start.

Experts called the discovery a major advance if confirmed by others. Although many scientists already believed that initial, extremely rapid growth spurt happened, finding this evidence has been a key goal in the study of the universe.

Researchers reported Monday that they did it by peering into the faint light that remains from the Big Bang.

Lawrence Krauss
If verified, the discovery "gives us a window on the universe at the very beginning," when it was far less than one-trillionth of a second old, said theoretical physicist Lawrence Krauss of Arizona State University, who was not involved in the work.

"It's just amazing," he said. "You can see back to the beginning of time."

Alan Guth
Another outside expert, physicist Alan Guth of the Massachusetts Institute of Technology (MIT), said the finding already suggests that some ideas about the rapid expansion of the universe can be ruled out.

Right after the Big Bang, the universe was a hot soup of particles.

It took about 380,000 years to cool enough that the particles could form atoms, then stars and galaxies.

Billions of years later, planets formed from gas and dust that were orbiting stars. The universe has continued to spread out.

This image provided by the BICEP2 Collaboration shows slight temperature fluctuations, indicated by variations in colour, of the Cosmic Microwave Background (CMB) of a small patch of sky and the orientation of its polarisation, shown as short black lines.

Researchers say since the CMB is a form of light, it exhibits all the properties of light, including polarisation. 

The changes in a particular type of polarisation, indicated here, are theorised to be caused by gravitational waves. 

These waves are signals of an extremely rapid inflation of the universe in its first moments. 

Credit: AP Photo/BICEP2 Collaboration

Krauss said he thinks the new finding could rank with the greatest discoveries about the universe over the last 25 years, such as the Nobel prize-winning discovery that the universe's expansion is accelerating.

The new results were announced by a collaboration that includes researchers from the Harvard-Smithsonian Center for Astrophysics (CfA), the University of Minnesota, Stanford University, the California Institute of Technology (CalTech) and NASA's Jet Propulsion Laboratory.

The team plans to submit its results to a scientific journal this week, said its leader, John Kovac of Harvard.

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