That procedure would seem to render it impossible for LIGO researchers to know for 3 months whether they had a real signal or not.
Krauss acknowledges the point, but says that in September 2015 a prominent physicist told him that the LIGO team had spotted the signal in data from an engineering run, into which—he claims—false signals are not injected. However, that physicist is not a member of the LIGO collaboration, Krauss says, so the information is second-hand at best.
More recently, Krauss says, others have told him that the LIGO team is writing a paper and debating whether a potential signal fits the signal expected from a pair of neutron stars spiraling together or a pair of black holes spiraling together. Again, Krauss says, the sources of these additional rumors do not work within the LIGO collaboration.
Krauss has taken some blowback for his rumor-mongering. "[I]f true, you are trying to steal their glory; if false, you are damaging scientific credibility," tweeted Michael Merrifield, an astronomer at the University of Nottingham, in the United Kingdom. Erik Mamajek, an astronomer at the University of Rochester in New York tweeted, "Does [the LIGO] project sanction your rumor-mongering? 'Confirmed' followed by 'may have been' = BS. Hurts science."
Krauss, the author of nine popular science books including The Physics of Star Trek and A Universe from Nothing, counters that he was merely trying key in the public to the discussions physicists are already having among themselves. "All I was trying to do was prepare people for the potential excitement," he says. "If something really excites me, should I never talk about it?"
LIGO leaders seem somewhat dismayed by whole affair. "I’ve seen Krauss’s new tweet," wrote Gabriela Gonzalez, a physicist at Louisiana State University, Baton Rouge, and spokesperson for the LIGO Scientific Collaboration in an email. "I’m disappointed (again) that he didn’t ask me or anybody in LIGO leadership."
Krauss says that he purposefully avoided trying to confirm the rumors because doing so would have been unethical. "If I contacted them, that would imply that I was trying to get information I shouldn't have," he says. "That would have been inappropriate." Krauss adds that, had he been told something by LIGO researchers in confidence, he would have kept it to himself.
For their part, LIGO researchers declined to comment on the purported signal. "We have not finished taking data yet and haven’t finished reviewing analysis of results even from early in the run," Gonzalez says. "We’ll certainly let you know when we have news to share." And that’s no rumor.