NEW YORK — Scientists who made headlines last March by announcing that they’d found long-sought evidence about the early universe are now abandoning that claim.

The original announcement caused a sensation because it appeared to show evidence that the universe ballooned rapidly a split-second after its birth, in what scientists 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 is 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, “we are effectively retracting the claim,” said Brian Keating of the University of California, San Diego, a member of the BICEP2 team.

In essence, Keating said, the analysis shows that the source of the signal observed by BICEP2 isn’t necessarily the very early universe.

Instead, it’s equally likely to have come from dust in our galaxy, which would mean it does not provide the evidence BICEP2 had claimed.