[Here at the Aspen Center Champagne in the wee hours as word arrived via Webcast from CERN. It was a scene duplicated in Melbourne, Australia, where physicists had gathered for a major conference, as well as in Los Angeles, Chicago, Princeton, New York, London and beyond — everywhere that members of a curious species have dedicated their lives and fortunes to the search for their origins in a dark universe.]
By Dennis Overbye
Like Omar Sharif materializing out of the shimmering desert
as a man on a camel in “Lawrence of Arabia,” the elusive boson has been coming
slowly into view since last winter, as the first signals of its existence grew
until they practically jumped off the chart.
“I think we have it,” said Rolf-Dieter Heuer, the director
general of CERN, the multinational research center
headquartered in Geneva
He and others said that it was too soon to know for sure,
however, whether the new particle is the one predicted by the Standard Model,
the theory that has ruled physics for the last half-century. The particle is
predicted to imbue elementary particles with mass. It may be an impostor as yet
unknown to physics, perhaps the first of many particles yet to be discovered.
That possibility is particularly exciting to physicists, as
it could point the way to new, deeper ideas, beyond the Standard Model, about
the nature of reality.
For now, some physicists are simply calling it a
“Higgslike” particle.
“It’s something that may, in the end, be one of the biggest
observations of any new phenomena in our field in the last 30 or 40 years,”
said Joe Incandela, a physicist of the University of California, Santa Barbara,
and a spokesman for one of the two groups reporting new data on Wednesday.
Here at the Aspen Center Champagne
In Geneva University of Edinburgh
Confirmation of the Higgs boson or something very much like
it would constitute a rendezvous with destiny for a generation of physicists
who have believed in the boson for half a century without ever seeing it. The
finding affirms a grand view of a universe described by simple and elegant and
symmetrical laws — but one in which everything interesting, like ourselves,
results from flaws or breaks in that symmetry.
According to the Standard Model, the Higgs boson is the
only manifestation of an invisible force field, a cosmic molasses that
permeates space and imbues elementary particles with mass. Particles wading
through the field gain heft the way a bill going through Congress attracts
riders and amendments, becoming ever more ponderous.
Without the Higgs field, as it is known, or something like
it, all elementary forms of matter would zoom around at the speed of light,
flowing through our hands like moonlight. There would be neither atoms nor
life.
Physicists said that they would probably be studying the
new particle for years. Any deviations from the simplest version predicted by
current theory — and there are hints of some already — could begin to answer
questions left hanging by the Standard Model. For example, what is the dark
matter that provides
the gravitational scaffolding of galaxies?
And why is the universe made of matter instead of
antimatter?
“If the boson really is not acting standard, then that will
imply that there is more to the story — more particles, maybe more forces
around the corner,” Neal Weiner, a theorist at New York
University
Wednesday’s announcement was also an impressive opening act
for the Large Hadron Collider, the world’s biggest physics machine, which cost
$10 billion to build and began operating only two years ago. It is still
running at only half-power.
Physicists had been icing the Champagne
Last winter, they both reported hints of the same particle.
They were not able, however, to rule out the possibility that it was a
statistical fluke. Since then, the collider has more than doubled the number of
collisions it has recorded.
The results announced Wednesday capped two weeks of
feverish speculation and Internet buzz as the physicists, who had been sworn to
secrecy, did a breakneck analysis of about 800 trillion proton-proton
collisions over the last two years.
Up until last weekend, physicists at the agency were saying
that they themselves did not know what the outcome would be. Expectations
soared when it was learned that the five surviving originators of the Higgs
boson theory had been invited to the CERN news conference.
The December signal was no fluke, the scientists said
Wednesday. The new particle has a mass of about 125.3 billion electron volts,
as measured by the CMS group, and 126 billion according to Atlas. Both groups
said that the likelihood that their signal was a result of a chance fluctuation
was less than one chance in 3.5 million, “five sigma,” which is the gold
standard in physics for a discovery.
On that basis, Dr. Heuer said that he had decided only on
Tuesday afternoon to call the Higgs result a “discovery.”
He said, “I know the science, and as director general I can
stick out my neck.”
Dr. Incandela’s and Dr. Gianotti’s presentations were
repeatedly interrupted by applause as they showed slide after slide of data
presented in graphs with bumps rising like mountains from the sea.
Dr. Gianotti noted that the mass of the putative Higgs,
apparently one of the heaviest subatomic particles, made it easy to study its
many behaviors. “Thanks, nature,” she said.
Gerald Guralnik, one of the founders of the Higgs theory,
said he was glad to be at a physics meeting “where there is applause, like a
football game.”
Asked to comment after the announcements, Dr. Higgs seemed
overwhelmed. “For me, it’s really an incredible thing that’s happened in my
lifetime,” he said.
Dr. Higgs was one of six physicists, working in three
independent groups, who in 1964 invented what came to be known as the Higgs
field. The others were Tom Kibble of Imperial
College London University
of Rochester Brown University
One implication of their theory was that this cosmic
molasses, normally invisible, would produce its own quantum particle if hit
hard enough with the right amount of energy. The particle would be fragile and
fall apart within a millionth of a second in a dozen possible ways, depending
upon its own mass.
Unfortunately, the theory did not describe how much this
particle should weigh, which is what made it so hard to find, eluding
researchers at a succession of particle accelerators, including the Large
Electron Positron Collider at CERN, which closed down in 2000, and the Tevatron
at the Fermi National Accelerator Laboratory, or Fermilab, in Batavia, Ill.,
which shut down last year.
Along the way the Higgs boson achieved a notoriety rare in
abstract physics. To the eternal dismay of his colleagues, Leon Lederman, the
former director of Fermilab, called it the “God particle,” in his book of the
same name, written with Dick Teresi. (He later said that he had wanted to call
it the “goddamn particle.”)
Finding the missing boson was one of the main goals of the
Large Hadron Collider. Both Dr. Heuer and Dr. Gianotti said they had not
expected the search to succeed so quickly.
So far, the physicists admit, they know little about their
new boson. The CERN results are mostly based on measurements of two or three of
the dozen different ways, or “channels,” by which a Higgs boson could be
produced and then decay.
There are hints, but only hints so far, that some of the
channels are overproducing the boson while others might be underproducing it,
clues that maybe there is more at work here than the Standard Model would
predict.
“This could be the first in a ring of discoveries,” said
Guido Tonelli of CERN.
In an e-mail, Maria Spiropulu, a professor at the
California Institute of Technology who works with the CMS team of physicists,
said: “I personally do not want it to be standard model anything — I don’t want
it to be simple or symmetric or as predicted. I want us all to have been dealt
a complex hand that will send me (and all of us) in a (good) loop for a long
time.”
Nima Arkani-Hamed, a physicist at the Institute for
Advanced Study in Princeton , said: “It’s a triumphant day for fundamental physics.
