An unassuming astrophysicist nabs the Nobel Prize—right in our own backyard.

At first glance, Saul Perlmutter doesn’t give off the vibe of a fiercely competitive man. The 52-year-old Berkeley astrophysicist is slim and bespectacled, and, if prompted, waxes poetic about his many cherished hobbies: reading to his 8-year-old daughter, folk dancing, playing violin and tennis—and his award-winning research on the cosmos.

You’d never guess by looking at him, but, for the better part of a decade, Perlmutter and his team at University of California, Berkeley, and Lawrence Berkeley National Laboratory were engaged in two intense battles—one against the clock, one against a rival team—as they worked by the dark of the moon, culling the secrets of distant intergalactic giants called supernovae.

Perlmutter, for those who missed the hubbub earlier this fall, is Cal’s latest golden boy.

He is one of three winners of this year’s Nobel Prize in physics, and this month will travel to Sweden to accept his award for disproving one of science’s most basic assumptions—that the expansion of the universe is slowing down—and revealing a bleak, previously unknown cosmological force known as dark energy.

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Born in Illinois and raised in Philadelphia, Perlmutter graduated from Harvard University in 1981, then pursued a Ph.D. in physics at U.C. Berkeley—a place which “felt like it was off the ends of the earth,” Perlmutter recalls. “I told myself, ‘It’s only a few years.’”

In 1986, the university and Lawrence Berkeley National Laboratory asked the newly minted Dr. Perlmutter to stay on to do research, and, eventually, to lead the Supernova Cosmology Project, which he co-founded with renowned research physicist Carl Pennypacker in 1988. An international research team with 31 members from Australia, Chile, France, Spain, Sweden, the United Kingdom, and the United States, the Supernova Cosmology Project was designed to study the fate of the universe by looking at the luminosity of exploding stars (supernovae).

“A few years turned into a few more years and a few more years after that,” Perlmutter says. “I always thought it was temporary. I guess I’m here to stay.”

Three decades after his arrival, Perlmutter still lives in Berkeley, with his wife, anthropology professor Laura Nelson, who teaches at Cal State East Bay, and their daughter, Noa, who attends elementary school in El Cerrito.

When Perlmutter launched the Supernova Cosmology Project, it was widely accepted that after the Big Bang, the universe began expanding, but at an ever-decreasing speed. In other words, the universe is getting bigger, but the rate at which it is expanding was thought to be slower today than it was yesterday, and slower tomorrow than it is today.

When Perlmutter began his research, his team simply wanted to see how quickly the expansion was slowing. They thought they could even determine whether it would someday stop, causing the universe to reverse course and collapse on itself in an event dubbed the Big Crunch.

In the mid-1990s, another research team, the High-z Supernova Search Team at Australian National University—headed by Brian Schmidt and Adam Riess—arrived on the scene with its sights set on the same goal: to track the universe’s deceleration.

“There was definitely a sense of competition,” says Perlmutter. “We’d been working about six years on these distant supernovae when Schmidt and his team started their distant supernova project.” Adding to the sense of rivalry, both teams used the same telescopes—the University of California’s and California Institute of Technology’s Keck Telescope in Hawaii, the National Optical Astronomy Observatory’s telescopes in Chile and Arizona, and, later, NASA’s Hubble Space telescope. “We’d actually be passing each other at the telescopes,” he says.

“It was a real race, sometimes fiercely fought,” Perlmutter says, but he acknowledges that the teams had a camaraderie that can only exist between those who share enemies: in this case, unpredictable weather and the changing phases of the moon, which, when full, would outshine the supernovae. “I still have a hard time seeing a full moon,” he jokes.

“Everyone knew we were fierce rivals,” Perlmutter says. “One cosmologist made the comment that, ‘You guys are in such violent agreement.’” But “we recognized what the other team was doing and going through,” he says. “Once they got clouded out so we took data for them the next night. And once we got clouded out, and Brian switched upcoming nights with me.”

Despite the frustrations, Perlmutter says, there was always a sense of progress. In 1997, his team begain examining the results of the previous few years’ data.

“We finally reached a point when we started plotting the data,” he says. “You never believe just one supernova. You can still be unsure with a half dozen. But when we had 42 telling us the same thing, that was some-thing else.”

What the supernovae were saying was that the universe wasn’t in danger of collapse; in fact, it wasn’t slowing down at all.

Once upon a time, after the Big Bang, “things in the universe were close together and gravity would have been strong enough to slow the expansion down,” Perlmutter says. “But once the universe diluted” and planets, stars, asteroids, and other particles in space grew further apart, he says, another force stronger than gravity—so-called dark energy—took control and caused the expansion to accelerate.

Not much is known about dark energy, the mysterious force that sounds like it was pulled straight out of a sci-fi/horror novel, but scientists now believe it makes up 70 percent of the universe. Dark energy can’t be seen, felt, heard, or sensed in any way; the only sign of its existence is the effect measured by charting changes in the distances of far galaxies, tracked using supernovae that exploded in them.

In the long term, this means that the Big Crunch is less likely than a deep freeze. As the universe expands, the distance between celestial bodies that provide light and heat—and, in at least one case, life—grows as well. This means the universe of the future will be dark, cold, and much lonelier than previously imagined.

“It was shocking,” says Perlmutter. “First you think, ‘This is a big deal.’ Then you go back to thinking how you might be making a mistake.”

Perlmutter and his team checked their results and updated their numbers, but “the more we checked, the more the results didn’t go away,” he says.

Both the Berkeley and Australia teams reached the same conclusion at about the same time in late 1997 to early 1998, and began making the rounds, presenting their findings to their peers.

Reactions, at first, were mixed; scientists were reluctant to accept that their long-held belief about the universe was wrong.

But the competition finally paid off for both the Supernova Cosmology Project and the High-z Supernova Search Team. In 1998, the independent findings of both teams were jointly named “breakthrough of the year” by the journal Science. Astronomical Journal published Schmidt and Riess’s findings first, in November 1998, and Perlmutter’s results in June 1999.

Perlmutter won the California Scientist of the Year award in 2003, the Gruber Cosmology Prize in 2007, and the Albert Einstein Medal earlier this year, among other awards, several of them shared with Schmidt and his team.

But, he says, he never thought at the outset that this project would win him a Nobel Prize.

The story of how Perlmutter found out about his win has gained a certain amount of notoriety as it’s been recounted by media worldwide. Early in the morning of Oct. 4, members of the Royal Swedish Academy of Science, which awards the prize, tried in vain to call Perlmutter, dialing an outdated cell phone number.

It was a Swedish journalist, looking for a comment, who reached a sleepy and stunned Perlmutter; his wife looked up the announcement online to confirm the good news.

Finally, 45 minutes later, the academy members successfully made the official call.

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The two months since the announcement have been a whirlwind, says Perlmutter, who, long famous within the physics community, has not only been bombarded by requests for interviews and speaking engagements, but has became a pop culture sensation overnight.

In October, he even got a shout-out on the CBS sitcom, The Big Bang Theory, in which one of the characters, Sheldon Cooper, proposes taking his visiting mother to a Perlmutter lecture and staying for the question-and-answer portion of the talk.

“I’ve worked up a couple of Q’s that’ll stump his sorry A,” Sheldon says. After all, he adds, “What sight is better than seeing your little boy embarrass a Nobel laureate?”

This month, Perlmutter and his family will spend about 10 days in Sweden for the Nobel Prize awards ceremony on Dec. 10. He isn’t worried about the cold or the near-constant darkness as the winter solstice approaches; he’s concerned, he says, that his daughter will be bored.

Perlmutter will receive half of the $1.5 million prize, and Schmidt and Riess will share the other half.

Primetime television debut and $750,000 aside, Perlmutter says that some of his favorite moments happened in the hours immediately after the announcement, sandwiched between phone calls and news conferences, as he celebrated with his wife, daughter, and extended Cal “family” on the Berkeley campus.

“Berkeley is one of the few places where you could do this kind of work,” says Perlmutter. “You walk up and down the halls and find all these experts and a culture that is very open to new ideas and developing new approaches.”

Perlmutter adds that one of the unique aspects of being a researcher at U.C. Berkeley is the university’s relationship with Lawrence Berkeley National Laboratory. The lab is managed by the University of California, but as a part of the national laboratory system, it receives financial support from the U.S. Department of Energy’s Office of Science. Many U.C. Berkeley students do their research at the lab, located in the hills overlooking the university.

“You can do things [here] that would be hard to do at a university on its own,” Perlmutter says. “Also, not many places would have stuck with us this long,” he adds with a laugh, noting that the decade-long project was only slated to take three years.

Perlmutter’s Nobel Prize is the 11th at the Lawrence Berkeley National Laboratory, and the 22nd awarded to a U.C. Berkeley faculty member. In addition to international fame and glory, he is now entitled to a coveted reserved parking spot on campus—“the only reason to win a Nobel Prize,” he has joked.

He’s counting on his family to make sure the attention and perks don’t go to his head. “I think my daughter got a kick out of all this that first day,” Perlmutter says. “But she had a rather interesting comment that night. She said, ‘Can you talk to the part of my brain that thinks you’re a different person now?’ So I told her a night-night story, and called it a day.”

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Maggie Fazeli Fard, formerly the vice president of her high school’s astronomy club and a graduate of U.C. Berkeley’s Graduate School of Journalism, now writes for The Washington Post. She is a frequent contributor to The Monthly.