From AP via Yahoo! News:
Eureka! Physicists celebrate evidence of particle
Scientists at the world's biggest atom smasher
hailed the discovery of "the missing cornerstone of physics" Wednesday,
cheering the apparent end of a decades-long quest for a new subatomic particle called the Higgs boson, or "God particle," which could help explain why all matter has mass and crack open a new realm of subatomic science.
First
proposed as a theory in the 1960s, the maddeningly elusive Higgs had
been hunted by at least two generations of physicists who believed it
would help shape our understanding of how the universe began and how its
most elemental pieces fit together.
As
the highly technical findings were announced by two independent teams
involving more than 5,000 researchers, the usually sedate corridors of
the European Center for Nuclear Research, or CERN, erupted in frequent
applause and standing ovations. Physicists who spent their careers in
pursuit of the particle shed tears.
The new particle appears to share many of the same qualities as the one predicted by Scottish physicist Peter Higgs
and others and is perhaps the biggest accomplishment at CERN since its
founding in 1954 outside Geneva along the Swiss-French border.
Rolf
Heuer, director of CERN, said the newly discovered particle is a boson,
but he stopped just shy of claiming outright that it is the Higgs boson
itself — an extremely fine distinction.
"As
a layman, I think we did it," he told the elated crowd. "We have a
discovery. We have observed a new particle that is consistent with a
Higgs boson."
The Higgs, which
until now had been purely theoretical, is regarded as key to
understanding why matter has mass, which combines with gravity to give
all objects weight.
The idea is much like gravity and Isaac Newton's
early theories. Gravity was there all the time before Newton explained
it. The Higgs boson was believed to be there, too. And now that
scientists have actually seen something much like it, they can put that
knowledge to further use.
The
center's atom smasher, the $10 billion Large Hadron Collider, sends
protons whizzing around a circular 27-kilometer (17-mile) underground
tunnel at nearly the speed of light to create high-energy collisions.
The aftermath of those impacts can offer clues about dark matter,
antimatter and the creation of the universe, which many theorize
occurred in a massive explosion known as the Big Bang.
Most
of the particles that result from the collisions exist for only the
smallest fractions of a second. But finding a Higgs-like boson was one
of the biggest challenges in physics: Out of some 500 trillion
collisions, just several dozen produced "events" with significant data,
said Joe Incandela of the University of California at Santa Barbara, leader of the team known as CMS, with 2,100 scientists.
Each
of the teams confirmed Wednesday that they had "observed" a new
subatomic particle — a boson. Heuer said the discovery was "most
probably a Higgs boson, but we have to find out what kind of Higgs boson
it is." He referred to the discovery as a missing cornerstone of
science.
As the leaders of the two teams presented their evidence, applause punctuated their talks.
"Thanks,
nature!" joked Fabiola Gianotti, the Italian physicist who heads the
team called ATLAS, with 3,000 scientists, drawing laughter from the
crowd.
Later, she told
reporters that the standard model of physics is still incomplete because
"the dream is to find an ultimate theory that explains everything. We
are far from that."
Incandela
said it was too soon to say definitively whether the particle was
exactly the same as envisioned by Higgs and others, who proposed the
existence of an energy field where all particles interact with a key
particle, the Higgs boson.
Higgs, who was invited to be in the audience, said Wednesday's discovery appears to be close to what he predicted.
"It
is an incredible thing that it has happened in my lifetime," he said,
calling the discovery a huge achievement for the proton-smashing
collider.
Outside CERN, the announcement seemed to ricochet around the world with some of the speed and energy of the particle itself.
In
an interview with the BBC, the world's most famous physicist, Stephen
Hawking, said Higgs deserved the Nobel Prize. Hawking said he had placed
a wager with another scientist that the Higgs boson would never be
found.
"It seems I have just lost $100," he said.
Marc
Sher, a professor of physics at William & Mary College, said most
observers concluded in December that the Higgs boson would soon be
discovered, but he was "still somewhat stunned by the results."
The
phrase "God particle" was coined by Nobel Prize-winning physicist Leon
Lederman, but it's used mostly by laymen as an easier way of explaining
the theory.
Wednesday's
celebration was mainly for researchers who explore the deepest, most
esoteric levels of particle science. But the particle-hunting effort has
paid off in other ways for non-scientists, including contributing to
the development of the World Wide Web.
CERN
scientists used the early Web to exchange information, and the vast
computing power needed to crunch all of the data produced by the atom smasher also boosted development of cloud computing, which is now making its way into mainstream services.
Advances
in solar energy, medical imaging and proton therapy used in the fight
against cancer have also resulted from the work of particle physicists at CERN and elsewhere.
The
last undiscovered piece of the standard model of physics could be a
variant of the Higgs that was predicted or something else that entirely
changes the way scientists think about how matter is formed, Incandela
said.
"This boson is a very profound thing we have found," he
said. "We're reaching into the fabric of the universe in a way we never
have done before. We've kind of completed one particle's story. ... Now
we're way out on the edge of exploration."
The discovery is so
fundamental to the laws of nature, Incandela said, that it could spawn a
new era of technology and development in the same way that Newton's
laws of gravity led to basic equations of mechanics that made the
industrial revolution possible.
"This is so far out on a limb, I
have no idea where it will be applied," he added. "We're talking about
something we have no idea what the implications are and may not be
directly applied for centuries."
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