Has cosmic inflation theory been deflated?

Researchers have found that the highly publicized BICEP2 findings, which lent support to the theory that the universe rapidly expanded in the first few moments after the Big Bang, might be flawed.

|
ESA/Planck Collaboration
Map showing the tiny variations in the cosmic microwave background (CMB) observed by Europe's Planck satellite.

One of the most exciting astrophysics discoveries in recent memory may be a mirage.

In March, a team of scientists announced that they had found evidence of primordial gravitational waves, hypothesized ripples in space-time whose existence would suggest that the universe did indeed expand many times faster than the speed of light in the first few instants after the Big Bang, as posited by the "cosmic inflation" theory.

But some outside researchers quickly raised questions about the discovery, which was made using observations by the Background Imaging of Cosmic Extragalactic Polarization (BICEP2) telescope in Antarctica. The supposed gravitational-wave signal, the skeptics said, may actually be a contaminant, the result of dust and gas within our own Milky Way galaxy. [The Big Bang to Now in 10 Easy Steps]

The BICEP2 team saw a polarization pattern known as "B modes" in the cosmic microwave background(CMB), the ancient light left over from the Big Bang that created the universe 13.8 billion years ago. Wide acceptance of the purported find will likely come only if other instruments pick it up, too — in particular, the European Space Agency's Planck satellie, which mapped out the CMB in fine detail from 2009 to 2013.

The Planck team has indeed followed up the BICEP2 result, analyzing data from the same patch of sky in a variety of frequencies that range from 30 gigaherz to 857 gigaherz. (BICEP2 looked in just a single frequency, 150 gigaherz.) And the news is not great for the BICEP2 crew, a new study reports.

"Unfortunately, according to our analysis, the effect of contaminants and in particular of gases present in our galaxy cannot be ruled out," co-author Carlo Baccigalupi of the International School for Advanced Studies in Trieste, Italy, said in a statement.

The new study does not rule out the possibility that BICEP2 really did see the signature of primordial gravitational waves, however. Indeed, Planck scientists are working with the discovery team to see if this could be the case.

"We have started a collaboration with BICEP2. We are directly comparing their data with the Planck data, in the same frequency, 150 GHz, and trying to exploit the image of the contaminants we reach with Planck at other frequencies," Baccigalupi said. ?"This way, we hope to be able to give a definitive answer. In fact, we might find that it was indeed a contamination, but, given that we’re optimists, we might even be able to exclude it with confidence."

If the discovery is confirmed, Baccigalupi added, it "would open a completely new window onto unknown scenarios in the study of the primordial universe and very-high-energy physics."

The new study from the Planck team will be published Monday (Sept. 29) in the journal Astronomy & Astrophysics. You can read a preprint of it here: http://arxiv.org/abs/1409.5738

Follow Mike Wall on Twitter @michaeldwall and Google+. Follow us @SpacedotcomFacebook orGoogle+. Originally published on Space.com.

Copyright 2014 SPACE.com, a TechMediaNetwork company. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

You've read  of  free articles. Subscribe to continue.
Real news can be honest, hopeful, credible, constructive.
What is the Monitor difference? Tackling the tough headlines – with humanity. Listening to sources – with respect. Seeing the story that others are missing by reporting what so often gets overlooked: the values that connect us. That’s Monitor reporting – news that changes how you see the world.

Dear Reader,

About a year ago, I happened upon this statement about the Monitor in the Harvard Business Review – under the charming heading of “do things that don’t interest you”:

“Many things that end up” being meaningful, writes social scientist Joseph Grenny, “have come from conference workshops, articles, or online videos that began as a chore and ended with an insight. My work in Kenya, for example, was heavily influenced by a Christian Science Monitor article I had forced myself to read 10 years earlier. Sometimes, we call things ‘boring’ simply because they lie outside the box we are currently in.”

If you were to come up with a punchline to a joke about the Monitor, that would probably be it. We’re seen as being global, fair, insightful, and perhaps a bit too earnest. We’re the bran muffin of journalism.

But you know what? We change lives. And I’m going to argue that we change lives precisely because we force open that too-small box that most human beings think they live in.

The Monitor is a peculiar little publication that’s hard for the world to figure out. We’re run by a church, but we’re not only for church members and we’re not about converting people. We’re known as being fair even as the world becomes as polarized as at any time since the newspaper’s founding in 1908.

We have a mission beyond circulation, we want to bridge divides. We’re about kicking down the door of thought everywhere and saying, “You are bigger and more capable than you realize. And we can prove it.”

If you’re looking for bran muffin journalism, you can subscribe to the Monitor for $15. You’ll get the Monitor Weekly magazine, the Monitor Daily email, and unlimited access to CSMonitor.com.

QR Code to Has cosmic inflation theory been deflated?
Read this article in
https://www.csmonitor.com/Science/2014/0924/Has-cosmic-inflation-theory-been-deflated
QR Code to Subscription page
Start your subscription today
https://www.csmonitor.com/subscribe