Physicists find Big Bang’s smoking gun

U researchers found gravitational waves that support the Big Bang Theory.

Physicists find Big Bang’s smoking gun

Kristoffer Tigue

University of Minnesota physicists, along with a nationwide team of researchers, say they’ve discovered the first evidence that can explain some decades-old mysteries about the infantile stages of the universe.

They’ve observed the mark of gravitational waves that provide the first evidence of how the universe expanded uniformly and almost instantaneously after the Big Bang 13.8 billion years ago. Researchers announced the finding last month.

“We have discovered what looks very much like the expected signature of gravitational waves, spawned in the first tiny, tiny fraction of a second by the process called inflation,” said lead researcher and University physics associate professor Clem Pryke.

Inflation theory explains how the universe, which was once a tiny subatomic speck, expanded to its current size in such a short amount of time. The gravitational waves are the first evidence to support the theory, which helps explain many of the features of today’s universe.

“We’ve been trying to find evidence for inflation for decades,” said Terry Jones, director of graduate and undergraduate studies at the Minnesota Institute for Astrophysics. “We’ve all just grown up assuming it took place … but with no real hard evidence. And this is the first smoking-gun evidence that inflation took place.”

Jones works in the E and B Experiment at the University, which was looking for the same gravitational waves that Pryke’s group found.

Jones said he’s glad the evidence was discovered, even if it wasn’t by his team, and that he believes this is the most important scientific discovery of the year.

“What we have at the moment is evidence that inflation did take place,” he said. “Now that we have this, we can … come up with more robust ideas of what inflation was all about. What happened?”

His lab is working on confirming Pryke’s data to make sure it is as accurate as possible. Pryke’s group found the waves with a certainty of 5.9-sigma, meaning there’s only a one in 550 million chance that they observed what they did by random chance.

Stefan Fliescher is working on his post-doctorate with Pryke and did data analysis for the project, which gathered its information from the BICEP2 telescope at the South Pole.

Fliescher called the project “an adventure,” but he said the schedule and logistics of running were sometimes difficult due to time constraints.

The telescope is about the size of a bus, he said, and it has to run for eight consecutive months without maintenance because Antarctica gets too cold for planes to operate safely during the winter. Much of the work the team did during the summer was maintaining the telescope to keep it operational while they were away.

Community reaction

Society of Physics Students President Chris Nolting got the news of the discovery when he was on a trip to Duluth with 15 other physics students. They spent their lunch hour talking about what it means for the field.

Nolting said he hopes the discovery leads to better explanations of how gravity works at a subatomic level.

“It’s very exciting. There’s been so many really cool discoveries in physics in the last couple years,” he said. “It’s just an amazing time to be a physicist, to be studying physics.”

Chemistry graduate student Tom Fielitz is a practicing Christian, and he said this evidence is just another way for him to merge his scientific beliefs with his religious ones.

He said he doesn’t think his spiritual and scientific beliefs have to conflict.

“With this Big Bang stuff, this is fantastic, but how did all that get there to begin with?” he said. “You just kind of go through another series of questions.”

Fliescher said he thinks it’s “surprising” that humankind is even capable of thinking about something as grand as the beginning of the universe, so to be able to take measurements from that time period and find evidence like this is “an amazing thing.”

“It definitely gives us more confidence in our thinking of the universe,” he said. “There’s a lot of theories out there. Now, for the first time, we know … what we were thinking is true.”