Alan Guth. Photo: Justin Knight Photography.
MIT physics professor Alan Guth. Photo: Justin Knight Photography.

Giddy physicists and friends packed an MIT auditorium March 18 to celebrate one of the biggest breakthroughs ever in their field: the first direct evidence of what happened in the first fraction of a second after the birth of our universe.

Alan Guth ’68, PhD ’72, Victor F. Weisskopf Professor of Physics, beamed as he strode the aisles distributing bottles of sparkling cider to toast the discovery, which confirms a theory he proposed in 1979. In that theory, known as cosmic inflation, the universe expanded exponentially, stretching far beyond the view of our best telescopes, within a tiny sliver of time after its birth.

Guth and several other cosmological luminaries—including seven members of the team led by Harvard physicists that announced the discovery at a press conference a day earlier—were on hand for a lecture by Andrei Linde of Stanford about the work. Linde himself is another pioneer of cosmic inflation.

In his talk, which often elicited laughs and clapping from the crowd, Linde described his first reaction to the signal indicating the first evidence of ripples in spacetime known as gravitational waves. “I couldn’t believe the data at first [because] it was such a strong signal,” he said. He compared it to searching for a needle in a haystack and finding a crowbar.

Physicists from around the world have applied many superlatives to the work. “This is one of the most important scientific discoveries of all time,” Max Tegmark, another MIT professor of physics, told the New York Times.

What’s next? After the talk, MIT Professor of Physics Janet Conrad told Continuum, “We need more experiments to confirm [the results]. It’s a beautiful experiment, but any experiment needs multiple cross checks.” The nice thing, she points out, is that there are already many other experiments underway to do just that.

In the meantime, physicists are ecstatic. Linde concluded his talk with a slide titled “tentative conclusion.” His answer? “WOW. What a great time to be a cosmologist.”

From the MIT News Office: Three Questions with Alan Guth.

Watch: Chao-Lin Kuo, a Stanford colleague and a member of the Harvard team, surprised Andrei Linde at home with the news: