The BICEP2 team have officially published their results. They had announced to much fanfare back in March, that they had detected primordial gravitational waves, and hence cosmic inflation. But the results have increasingly been met with doubt, primarily centered on the possibility of interstellar dust causing the observed results.
From a New Scientist article on the published paper:
It was hailed as the discovery of the century. But now the researchers who earlier this year reported the first detection of primordial gravitational waves – ripples in space time hailing from the early universe – say they are not so sure after all.
“Has my confidence gone down? Yes,” says Clement Pryke of the University of Minnesota, co-leader of the team that reported the original result.
In March, the team, which uses a telescope called BICEP2 based at the South Pole, announced their discovery at the Harvard Center for Astrophysics in Cambridge, Massachusetts. They also posted their results online.
Today, the first peer-reviewed version of their results appears in the journalPhysical Review Letters – and it backtracks on the certainty of the original announcement.
None of this means that gravitational waves, or cosmic inflation, is disproven. The other experiments racing to find evidence may come up with independent results soon. But in science, nothing is settled until the data is in, and the results have been extensively replicated and accepted.