BICEP2 CMB gravity wave inflationThese swirls in the cosmic microwave background show the effect of primordial gravitational waves.BICEP2
Scientists, on the whole, are a circumspect lot. When faced with a microphone or reporter’s notepad, most of them (excepting a vocal minority) hedge and temper their language, adding provisos and qualifications, burying significant news behind accurate but unexciting jargon. So when they break out of that mold en masse and start making big claims in bold language, it’s usually a good time to listen.
This is exactly what happened yesterday after a news conference on results from BICEP2, a detector in Antarctica that measures the cosmic microwave background, an afterglow from the Universe’s early period. The team running the experiment there announced that they had turned up solid evidence of “primordial” gravitational waves that emerged when the universe was just 10-37 seconds old, compressed into a minuscule scale, with unfathomably high energies. The waves not only afford us a closer look than ever before at what happened at the moment of the birth of the Universe, but also lend strong support to inflation, a leading theory of how the Universe seems to have grown so quickly in its infancy and why it’s structured the way it is today.
In some very well-reported articles on this deservedly heavily covered event, the excitement of physicists practically leaps out. But even at this time of elation, they remind us that major announcements, even form the most careful researchers, must be exhaustively confirmed and analyzed and tested before they enter the pantheon of experimentally proven truths. The quotes below illustrate these two sides of the reaction to what may be a truly historic discovery.