[Vision2020] 2011 Nobel in Physics: Mysterious "Dark Energy" Accelerating Expansion of Universe

[Ted Moffett]

According to the accelerating universe expansion explored by these
Nobel winning scientists, in a trillion years the distance between
galaxies will be greater than the current size of the entire universe.
 "Dark" energy indeed!  The "Big Rip" might be the eventual end, with
even atoms "ripping" apart...

http://abclocal.go.com/kfsn/story?section=news/technology&id=8378877

3 win Nobel for showing universe is speeding up

Tuesday, October 04, 2011
By MALCOLM RITTER and KARL RITTER

NEW YORK -- Three U.S.-born scientists won the Nobel Prize in physics
Tuesday for discovering that the universe is expanding at an
accelerating pace, a stunning revelation that suggests the cosmos
could be headed for a colder, bleaker future, nearly devoid of light.

In 1998, Saul Perlmutter, Brian Schmidt and Adam Riess presented
findings that overturned the conventional idea that the expansion was
slowing 13.7 billion years after the big bang.

Their discovery raised a question: What is pushing the universe apart?
Scientists have labeled it "dark energy," but nobody knows what it is.

It's "an enigma, perhaps the greatest in physics today," the Nobel
committee said.

Perlmutter, 52, of the Lawrence Berkeley National Laboratory and
University of California, Berkeley, will receive half the $1.5 million
prize. The other half will go to Schmidt, 44, at the Australian
National University in Weston Creek, Australia, and Riess, 41, an
astronomy professor at Johns Hopkins University and Space Telescope
Science Institute in Baltimore.

Working in two teams, with Perlmutter heading one, they had raced to
measure the universe's expansion by analyzing light from dozens of
exploding stars called supernovas. They found the light was weaker
than expected, signaling that the expansion of the universe was
accelerating.

It was "one of the truly great discoveries in the history of science,
and one whose implications are not fully understood," said Paul
Steinhardt, a physics professor at Princeton University.

One consequence of the finding is that in a trillion years, galaxies
will be spread apart from each other by more than the current size of
the universe, he said. And the ever-greater expansion rate means the
light from one galaxy will no longer be visible from another as it is
today, he said.

"It's like changing from New York City to suddenly where everyone is
spread out across some huge desert and there's nothing around to
view," Steinhardt said.

The rapid expansion also implies that the universe will get
increasingly colder as matter spreads across ever-vaster distances in
space, said Lars Bergstrom, secretary of the Nobel physics committee.

The committee, citing the Robert Frost poem that pondered the world
ending in fire or ice, suggested that "if the expansion will continue
to speed up, the universe will end in ice."

But Robert Kirshner, a Harvard astronomer who was part of the team
that included his former students Schmidt and Riess, said scientists
don't know enough about dark energy to predict what will happen to the
universe hundreds of billions of years from now.

One possibility is that the expansion will continue to accelerate, he
said, "sort of like compound interest gone mad." It could even speed
up so much that not only will galaxies fly apart from each other, but
"stuff will really rip apart," even planets and atoms, he said. That's
called the "big rip," "and I hope that's not our fate."

On the other hand, Kirshner said, the expansion could halt and go into
reverse, so the universe collapses back into itself, a fate sometimes
called the "big crunch."

With such uncertainty, he said, "it seems very important to learn more
about what the dark energy is."

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
said. "My knees sort of went weak and I had to walk around and sort my
senses out."

Riess said his "jaw dropped" when he got an early morning call at his
home in Baltimore from a bunch of Swedish men and realized "it wasn't
Ikea," the Swedish furniture retailer. "I'm dazed," he said.

Perlmutter said his team 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 discovery confirmed an idea from Albert Einstein called the
cosmological constant. Einstein included this in his general theory of
relativity, a cornerstone of modern physics.

The Nobel Prizes were established in the will of Swedish industrialist
Alfred Nobel and have been awarded since 1901. The prizes are
presented to the winners every year on Dec. 10, the anniversary of
Nobel's death in 1896.
------

Karl Ritter reported from Stockholm. Louise Nordstrom and Malin Rising
in Stockholm, Kristen Gelineau in Sydney, Jessica Gresko in Washington
and Greg Moore in Phoenix contributed.

(Copyright ©2011 by The Associated Press. All Rights Reserved.)
------------------------------------------
Vision2020 Post: Ted Moffett