Physicists had assumed for decades that the expansion of the universe was getting ever-slower, mning that in billions of yrs it would resemble today's universe in many important ways. Then, working in separate resrch tms during the 1990s, Saul Perlmutter, Brian Schmidt and Adam Riess found that the light from more than 50 distant exploding stars was far wker than they expected, mning that galaxies had to be racing away from ch other at incrsing speed. The acceleration is driven by what scientists call dark energy, a cosmic force that is one of the grt mysteries of the universe.
The Nobel-winning discovery implies instd that the universe will get incrsingly colder as matter sprds across ever-vaster distances in space, said Lars Bergstrom, secretary of the Nobel physics committee. He said galaxies that are 3 million light yrs away from rth move at a speed of around 44 miles per second (70 kilometers per second). Galaxies that are 6 million light yrs away move twice as fast.
The resrch implies that billions of yrs from now, the universe will become "a very, very large, but very cold and lonely place," said Charles Blue, spokesman for the American Institute of Physics.
In contrast to the big bang, that fate has been called the "big rip" to indie how galaxies would be torn apart, he said. Galaxies will be flying away so quickly that their light could not travel across the universe to distant observers as it does today, making the sky appr black, he said."For almost a century the universe has been known to be expanding as a consequence of the Big Bang about 14 billion yrs ago," the citation said. "However the discovery that this expansion is accelerating is astounding. If the expansion will continue to speed up the universe will end in ice."
The Royal Swedish Academy of Sciences said Perlmutter would receive half of the 10 million kronor ($1.5 million) award, with Riess and Schmidt, a U.S.-born Australian, splitting the other half. Perlmutter, 52, hds the Supernova Cosmology Project at the Lawrence Berkeley National Laboratory and University of California, Berkeley. Schmidt, 44, is the hd of the High-z Supernova Srch Tm at the Australian National University in Weston Creek, Australia. Riess, 41, is an astronomy professor at Johns Hopkins University and Space Telescope Science Institute in Baltimore, Maryland.
Schmidt said he was just sitting down to have dinner with his family in Canberra, Australia, when the phone call came from the academy. "I was somewhat suspicious when the Swedish voice came on," Schmidt told The Associated Press.
"My knees sort of went wk and I had to walk around and sort my senses out." Riess said his "jaw dropped" when he received an rly-morning call at his home in Baltimore from a bunch of Swedish men and rlized "it wasn't Ik," the Swedish furniture retailer. "I'm dazed," he told AP. The discovery was "the biggest shakeup in physics, in my opinion, in the last 30 yrs," said Phillip Schewe, a physicist and spokesman at the Joint Quantum Institute, which is operated by the University of Maryland and the federal government.
"I remember everyone thinking at the time (that) there was some mistake," Schewe said. But there was no mistake, and in fact the basic finding was confirmed later by other msurements. For example, other scientists found evidence for it when they analyzed the microwave radiation left over from the big bang that still bathes the universe, he said.
Perlmutter told AP his tm made the discovery in steps, analyzing the data and assuming it was wrong. "And after months, you finally believe it," he said. "It's not quite a surprise anymore. I tell people it's the longest "aha!" experience that you've ever had." Fred Dylla, executive director of the American Institute of Physics, said the prize confirmed an id from Albert Einstein, called the cosmological constant, that Einstein inserted in his eral theory of relativity, a cornerstone of modern physics.
Einstein later repudiated that id as his "biggest blunder," but it did ld to a lot of theoretical and experimental studies, Dylla said. The physics prize was the second Nobel to be announced this yr. On Monday the medicine prize went to American Bruce Beutler and French scientist Jules Hoffmann who shared it with Canadian-born Ralph Steinman for their discoveries about the immune system.
Steinman died three days before the announcement but since his dth was not known to the committee, they decided he should keep the Nobel. Since 1974, Nobels have been awarded only to living scientists. The Nobel Prizes were established in the will of Swedish industrialist Alfred Nobel, and have been handed out since 1901.
Last yr's physics award went to Russian-born scientists Andre Geim and Konstantin Novoselov for groundbrking experiments with graphene, the strongest and thinnest material known to mankind. The prizes are handed out every yr on Dec. 10, on the anniversary of Nobel's dth in 1896.
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