Addendum/Update. On May 16, Nature ran a follow-up by Ron Cowen under the headline: gravitational wave discovery faces scrutiny.
There was lots of excitment last March when scientists announced they'd captured a long-predicted pattern in microwaves from the big bang, but as is often the case, many journalists wrote that the finding was revolutionary if true and then dropped the story. So what happened next? Did those microwave signals picked up with a South Pole telescope change our understanding of the universe’s birth, or is it all just a mistake?
This month a physicist/blogger prompted some reporters to revisit the big bang story when he announced that the heads of the project, known as BICEP2, had admitted to a fatal error. Turns out the reality is a little more complicated than that, with the team members standing by their results, but revealing just how many levels of interpretation and inference go into the claim that the blips they see in their detectors really reflect patterns in the radiation left over from the big bang.
The story is technically complicated. One of the key predictions of the big bang idea was that energy from the early universe could be detected in the form of a uniform afterglow of microwaves. Scientists found those in the 1960s, but the big bang theory didn’t quite square with other observations until scientists in the 1980s came up with a variation called inflation. Inflation predicted that those microwaves would be polarized in a certain way, and that’s allegedly what was discovered in March.
And the human side is complicated too. The scientists on the BICEP2 team made a judgment call last March with their decision to announce the discovery at a press conference.
The initial round of stories did carry some caveats that the discovery would have to be confirmed, but the emphasis was on the significance of the results, if true, and not on various ways the results might be wrong.
Results this prominent tend to get scrutinized, and some particularly pointed criticism appeared May 12 in a French blog called Résonaances. The post included some interesting questions about the interpretation of the results, and the rumor that team members had recanted.
At Science, Adrian Cho picked up the story on May 12, under the headline, Blockbuster Big Bang Result May Fizzle, Rumor Suggests.
It starts out with this lede:
The biggest discovery in cosmology in a decade could turn out to be an experimental artifact—at least according to an Internet rumor.
It’s a little hard to know what to make of this. Should we take an “internet rumor” seriously? Further down in the story, however, we learn that the cosmology community is raising some serious concerns.
The following day, New Scientist’s Lisa Grossman weighed in with Rumors Swirl Over Big Bang Ripple Find. The story starts with this:
Has the recent discovery of gravitational waves been reduced to dust? Not so fast.
On 12 May, however, a rumour emerged on the physics blog Résonaances that the BICEP2 team has already admitted defeat. The blogger, particle physicist Adam Falkowski at CERN, says he has heard through the scientific grapevine that the BICEP2 collaboration misinterpreted a preliminary Planck map in its analysis. That map, presented at a conference, showed many possible sources of polarised light. The team reportedly used the map assuming that it only charted dust.
And on May 14, Dan Vergano followed up on his National Geographic blog with Big Bang Discovery Comes Under Fire.
Here's the sub-head:
An acclaimed "smoking gun" discovery explaining the unfolding of the early universe faces rumors of a cosmic misfire.
In all three stories, the focus is on the rumor:
A different kind of story appeared in the Washington Post on May 16. Joel Achenbach’s story, Big Bang Backlash, focused not on the rumor but on serious questions surrounding the finding and the inherent difficulty in interpreting the data – especially the task of sorting out cosmic signals from those generated by dust in our galaxy. The story includes a whole slew of interviews – people on the team, their supporters, their rivals and several theorists. Why should non-scientists care? Because the way the story is unfolding says something about the nature of the scientific enterprise:
Science is a demanding and unforgiving business, and great discoveries are greeted not with parades and champagne but rather with questions, doubts and demands for more data. So it is that, in recent days, scientists in the astrophysics community have been vocalizing their concern that the South Pole experiment, known as BICEP2, may have detected only the signature of dust in our own galaxy.
It’s a difficult story to explain to lay readers with no particular interest in cosmology, but the crux of the problem could hardly be made more simply than this:
These doubters say, in effect, that rather than seeing the aftershock of the birth of the universe the scientists may have seen only some schmutz in the foreground, as if they needed to clean their eyeglasses.
(As a complete aside, the way he phrased this might remind some history buffs that a more literal form of schmutz was considered in the original discovery of the cosmic microwaves back in the 1960s. When radio astronomers Arno Penzias and Robert Wilson started picking up mysterious, unexplained static with their horn antenna, they had to rule out the possibility that it was caused by pigeon droppings. After cleaning off that schmutz, the static remained.)
The Achenbach story included some intriguing and sad details about the human side of the science, including one death of a major character in the drama:
He said the community as a whole suffered a tragic blow with the death of Andrew Lange, a mentor to many young scientists. Lange, a professor at Caltech, took his life in 2010 at the age of 52.
“The deterioration of the group was a very real, if in perspective trivial, consequence of his absence; I am quite sure that we wouldn’t be having this discussion were he still at the helm of the BICEP experiment,” Jones said in an e-mail.
We all know scientists are human – there's no need to prove this in covering science – but good stories manage to convey just how much the unpredictable drama of human life steers the history of science, influencing what gets discovered when, how discoveries are interpreted and announced to the public, and who gets the credit.
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