Just months after the huge announcement was made to the world, the scientists who claimed they had finally gathered evidence that confirmed the Big Bang theory now admit that they may have been a little hasty.
Back in March, researchers from the BICEP2 (Background Imaging of Cosmic Extragalactic Polarization) collaboration announced that they had direct evidence for cosmic inflation, which was the rapid expansion of the universe immediately after the Big Bang. By measuring the Cosmic Microwave Background, which is the polarized radiation assumed to be the afterglow of the Big Bang, they claimed that they identified gravitational waves in space-time which were the first tremors of the Big Bang. These waves rippled through space from around 400,000 years after the universe was born.
“Detecting this signal is one of the most important goals in cosmology today,” John Kovac, leader of the BICEP2 collaboration, said back in March.
Pretty much as soon as the announcement was made, scientists voiced apprehensions about the findings. Some researchers were concerned that they may have mistaken signals emitted from dust for the gravitational waves, despite the fact that the team spent 3 years analyzing the data to rule out errors.
“We know that galactic dust emits polarized radiations. We see that in many areas of the sky, and what we pointed out in our paper is that pattern they have seen is just as consistent with the galactic dust radiations as with gravitational waves,” theoretical astrophysicist David Spergel told AFP.
Sure enough, in the paper published just last week by the BICEP2 collaboration in Physical Review Letters, the team acknowledges that they cannot exclude the possibility that the signal could be coming from dust.
Spergel said that upcoming results from a competing group using the ESA’s Planck telescope should finally settle the matter. Planck looks at a much larger region of the sky than BICEP2 and also collects measurements in six frequencies rather than just 1.
“I think in retrospect, they should have been more careful about making a big announcement,” Spergel added.
[Via AFP and Physical Review Letters]