Physics Nobel for expanding Universe
Stockholm - A trio of astronomers won the Nobel Physics Prize on Tuesday for discovering that the expansion of the Universe is accelerating, a finding that implies that the cosmos will end in frozen nothingness.
The three are Saul Perlmutter and Adam Riess of the United States and US-Australian Brian Schmidt, who were honoured for findings that were - to their own admission - both a complete surprise and a little scary.
The trio looked at so-called type 1a supernovae to set down a benchmark for the movement of light on a cosmological scale.
This kind of supernova, also called a white dwarf, can in the matter of a few weeks emit as much light as an entire galaxy.
But to their astonishment, the laureates found through observations of more than 50 distant supernovae that light from the dying stars was weaker than expected, meaning they were further away than expected.
They concluded that the Universe was expanding at an accelerating rate after the Big Bang that created it some 14 billion years ago.
"The discovery that this expansion is accelerating is astounding," the Nobel jury said.
"If the expansion will continue to speed up the Universe will end in ice."
What may drive the acceleration is an enigmatic force called dark energy, thought to constitute about three-quarters of the Universe.
"The findings have helped to unveil a Universe that to a large extent is unknown to science," the committee said.
The jury compared the discovery to "throwing a ball up in the air, and instead of having it come back down, watching as it disappears more and more rapidly into the sky, as if gravity could not manage to reverse the ball's trajectory."
"Something similar seemed to be happening across the Universe," it said.
Perlmutter, born in 1959, who heads the Supernova Cosmology Project at the Berkeley National Laboratory in California, won half of the €1.08m prize.
Schmidt, 44, who heads the High-z Supernova Search Team at the Australian National University, shared the other half with Riess, 41, and a professor of Astronomy and Physics at the Johns Hopkins University in Baltimore, Maryland.
When hearing the news, Schmidt said winning "sort of feels like when my children were born".
He told Swedish public broadcaster SVT by phone from Australia that he was "weak in the knees, really excited, and somewhat, I guess, amazed by the situation. It's been a pretty exciting last half-hour."
A little scared
Referring to the discoveries, Schmidt said that he and Riess "were working very closely, talking on the phone all the time, trying to figure out this crazy result.
"We were frantically trying to sort out where we had gone wrong. So it was with a fair bit of trepidation that we wound up telling our group that the Universe seems to be speeding up. We were hoping everyone would be nice to us. It seemed too crazy to be right. We were a little scared."
Perlmutter told Swedish radio by phone the news of the prize was "wonderful.
"It's also wonderful to hear that it's shared with the other team, since it seems like such a community activity that we all did together," he added.
All three laureates shared the Shaw Prize in Astronomy (worth $1 million) in 2006. Riess and Perlmutter also won the Albert Einstein Medal in February this year.
The trio will receive their Nobel Prize at a formal ceremony in Stockholm on December 10, the anniversary of prize founder Alfred Nobel's death in 1896.
On Tuesday, Bruce Beutler of the United States, Luxembourg-born Frenchman Jules Hoffmann and Ralph Steinman of Canada shared the Nobel medicine award for insights into immunology.
But the jury was caught off guard when it discovered hours after announcing the prize that Steinman had died of pancreatic cancer on Friday aged 68.
According to prize regulations, the award cannot be given posthumously. But ultimately, the Nobel Assembly declared Steinman would remain a laureate given the "unique" situation.