Criticisms of the BICEP announcement are coming in, and could overturn the highly-publicized announcement that “inflation” has been discovered.
It was supposed to be a shoo-in for a Nobel Prize, but the shoe may not fit. Science Magazine and other sites have announced a potential fatal flaw in the March announcement that a signal confirming cosmic inflation (3/17/14) was detected from the Antarctic instrument site. In “Blockbuster Big Bang Result May Fizzle, Rumor Suggests,” Science Now explains that a crucial factor, foreground microwave “noise,” may not have been subtracted out properly.
To subtract the galactic foreground, BICEP researchers relied on a particular map of it generated by the European Space Agency’s spacecraft Planck, which mapped the CMB across the entire sky from 2009 until last year. However, the BICEP team apparently interpreted the map as showing only the galactic emissions. In reality, it may also contain the largely unpolarized hazy glow from other galaxies, which has the effect of making the galactic microwaves coming from any particular point of the sky look less thoroughly polarized than they actually are. So using the map to strip out the galactic foreground may actually leave some of that foreground in the data where it could produce a spurious signal, Falkowski explains. “Apparently, there is something that needs to be corrected, so at this point the BICEP result cannot be taken at face value,” he tells Science.
BICEP researchers are not ready to concede the point, however. Clement Pryke, a cosmologist at the University of Minnesota, Twin Cities, and a co-principal investigator for the BICEP team, acknowledges that the foreground map is an important and thorny issue. Part of the problem is that the Planck team has not made the raw foreground data available, he says. Instead, BICEP researchers had to do the best they could with a PDF file of that map that the Planck team presented at a conference. Moreover, Pryke says, conversations with members of the Planck team leave it uncertain exactly what is in the key plot. “It is unclear what that plot shows,” he says.
The upcoming Planck map of foreground “could make the BICEP signal go away,” the article says. Since the Planck results will not be published till October, nobody will know if the announcement was a blockbuster or a bust. Meanwhile, the BICEP team stands by their paper.
How could a team be so careless as to rely on a PDF file of a map, without knowing what it represents? Was this a rush to publish for fame? It happens. Remember the eagerness in the young cosmologist’s knock on Andrei Linde’s door to see his delight at apparently having his view of inflation confirmed? Scientists have egos like other people. The lure of priority or prize money can trump modesty. Now, all those positivist proclamations could come crashing down. We’ll have to wait and see.