Tuesday, May 13, 2014

Doubts about BICEP2 conclusions

NewScientist reports:
Has the recent discovery of gravitational waves been reduced to dust? Not so fast.

The news that ripples in space-time, called gravitational waves, had been spotted stunned the physics community earlier this year. This week, rumours began swirling that the scientists who reported the find have now admitted to making a mistake. The team missed a key detail in its analysis of galactic dust, the rumours suggest, making it more likely that the signal came from a source other than gravitational waves.

But the team's response to this claim is unequivocal: "We've done no such thing," says principal investigator John Kovac at Harvard University. The validity of the discovery won't be known until another group either supports or opposes their finding, which could happen later this year.

In March, the BICEP2 collaboration announced that it had seen an imprint on ancient cosmic light that it says was created by gravitational waves. Those waves are thought to be products of inflation, a period of rapid growth during the first sliver of a second after the big bang. The finding was hailed as a smoking gun for the theory of inflation – and as evidence that theories of a multiverse may be true.
See also Woit's blog. I have posted some skepticism about BICEP2 here and here.

I wonder why the so-called "skeptic" community isn't more skeptical about radical new announcements like the BICEP2. They are always denouncing things like homeopathy, which maybe have some slight placebo effect. I can believe that BICEP2 gives some evidence for inflation, but the talk about quantum gravity waves seems dubious to me. We should know more soon, when more results are reported.

1 comment:

  1. Gee, polarized space dust. Whew, I'm glad there's nothing in the universe that could be polarizing space dust except 'ripples in the yadda yadda yadda field', except our own planet's magnetosphere, or the sun, and the stars in our galaxy, the ambient background charge field, and other galaxies, and .... yeah, pretty much anything else that can produce electromagnetism. I also noticed there were no graphical overlays over the computer generated images of polarized dust to indicate the orientation of the polarized dust in relation to the night sky. If the dust happened to be more polarized in relation to the plane of the solar system or the galactic plane or core, I'm willing to bet more than a few people would say 'so what'? I'm no physicist and even I was asking: "How do you know what polarized the dust and how long ago?" and "Since when did hypothetical gravity waves become involved with polarizing particles of anything, much less dust?"

    Perhaps if there was honesty in advertising, BICEP2 could have been called GIGO instead. It would have been far closer to the truth and more fitting to what was really going on.