It was supposed to be a revolutionary breakthrough: last March, a team of scientists found what are known as primordial gravitational waves, or ancient ripples in space-time that would have been produced just moments after the Big Bang, stunning direct evidence of a theory most scientists already hold true.
Or had they? On Jan. 30, two teams of scientists — one operating a European Space Agency telescope and the other the team that submitted the original paper — have decided it was all just a mirage kicked up by ordinary space dust in our galaxy, thus debunking what had been one of the biggest discoveries of 2014, according to a report by the Economist.
Such gravitational waves had long been sought by astronomers, as it would confirm that long-held theory that the universe suddenly expanded rapidly just instants after it exploded into existence, inflating at faster than the speed of light.
Most scientists hold that it is true based on indirect evidence, but so far, no one had been able to provide hard, direct evidence that this is what happened.
It explains why the BICEP2 team had been so excited to stumble upon what it though were primordial gravitational waves, which would have been exactly the direct evidence needed. It would have also allowed cosmologist to settle some key questions about inflation theory, as there are differing opinions on the matter within the scientific community.
However, scientists immediately began to doubt the results soon after the paper was published, as they noted that thin clouds of dust in interstellar space can produce a similar signal. In order to verify that the signal came from primordial gravitational waves, researchers would need to identify and remove such signals from their data, but it appears BICEP2 hadn’t been able to do that, instead relying on the best available maps of interstellar dust.
ESA’s orbiting telescope Planck generated better data that was not available to BICEP2 at the time, and its data was featured in the paper to analyze the results of the paper published last year. The result was that when the dust is removed from the data, the signature disappears, dumping cold water on what had been thought to be an exciting discovery.
However, it won’t dull scientists’ zeal to keep seeking evidence of the primordial gravitational waves, as they believe they are out there somewhere. More telescopes will continue to hunt for them, and Planck’s abilities could assist in that effort.