London: A new analysis has dynamited a much-hyped discovery of primordial “gravitational waves” from the dawn of time.
Despite earlier reports of a possible detection, a joint analysis of data from ESA’s Planck satellite and the ground-based BICEP2 and Keck Array experiments has found no conclusive evidence of primordial gravitational waves.
Scientists revealed that interstellar dust caused more than half of the signal detected by the Antarctica-based BICEP2 experiment. The Planck spacecraft observations were not yet available in March 2014 when the BICEP2 science team made its announcement.
BICEP2, Planck and Keck all study the cosmic microwave background (CMB), or light that was left over from the Big Bang, and which can be seen in every direction in the sky.
One feature of the CMB that these experiments study was its polarization, or the orientation of the light waves. (This phenomenon might be familiar in the form of polarizing sunglasses, which take advantage of light waves’ orientation by blocking light that becomes polarized as it bounces off the surface of water.)
The original announcement March 2014 caused a sensation because it appeared to show evidence that the universe ballooned rapidly a split-second after its birth, in what scientist call cosmic inflation.
That idea had been widely believed, but researchers had hoped to bolster it by finding a particular trait in light left over from the very early universe.
That signal was what the researchers claimed they had found in observations of the sky taken from the South Pole, in a project called BICEP2.
But now, in a new paper submitted for publication, Brian Keating of the University of California, San Diego, a member of the BICEP2 team said that they were effectively retracting the claim.Â