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By James Glanz - New York Times
 Two
detectors in Antarctica have discovered minute patterns in a glow
from primordial gases, possible traces of the cosmic match that
ignited the Big Bang and led to the creation of the universe 14
billion years ago, astronomers announced here today.
The patterns,
astronomers said, were probably created by microscopic processes
— energy fluctuations at the quantum scale — that were
at work when the universe was a tiny fraction of a second old
and smaller than a human fist.
The new observations
do not see the quantum fluctuations directly, but instead have
found traces of colossal waves, much like sound waves, that the
fluctuations probably set in motion, roiling the young universe.
The results
rest on the most detailed observations ever made of a glow from
the hot gases of the early universe. That glow, called cosmic
microwave background radiation, carried an imprint of those waves
to the detectors on Earth.
The news comes
as a relief for astronomers, some of whom started to worry last
year that their basic picture of the origins of the universe might
be flawed, after detailed observations failed to find the wave
patterns.
"We see
the structure of the universe in its infancy," said Dr. John
Carlstrom, a University of Chicago astrophysicist who leads the
team operating the Degree Angular Scale Interferometer, or DASI
(pronounced daisy), a microwave detector at a South Pole research
station operated by the National Science Foundation.
Dr. Michael
Turner, a cosmologist at the University of Chicago who was not
involved in the measurements, said that the precise time the fluctuations
took place remained to be determined by future measurements, but
that the process was likely to have taken place in a fraction
of a second comparable to a decimal point followed by 32 zeros
and a 1.
"We are
living in the most exciting time ever in cosmology," he added.
Besides DASI,
which also involved astronomers at the California Institute of
Technology, the announcement today included the so-called Boomerang
team. This group flew a balloon-borne detector around Antarctica,
and includes astronomers from the United States, Italy, Canada
and Britain. Antarctica is excellent for such observations because
the air is thin and dry and does not strongly absorb microwave
radiation.
Dr. John Ruhl
of the University of California at Santa Barbara presented results
today for the Boomerang team. The announcements took place at
a meeting of the American Physical Society.
The Antarctica
studies were buttressed today when another group of researchers
reported that they had made less distinct observations of the
wave patterns from the United States. That team, called Maxima,
includes astronomers at the University of Minnesota and the University
of California at Berkeley.
The leading
theory of how the universe could have exploded out of the primordial
nothingness, known as the theory of inflation, predicts that the
quantum fluctuations should have rattled the universe in such
a way that it resonated like a vast organ pipe, with one main
tone, or wavelength, and a series of overtones or harmonics.
Last year,
the Boomerang team detected the main tone but found no clear evidence
for the overtones, raising the possibility that the inflation
theory could be wrong. Since much of the information about the
fluctuations, like their relative intensity and spectrum, would
reside in the characteristics of the overtones, those results
raised the prospect that few remnants of the initial spark might
be found.
Today, the
three teams announced that they had seen two of the overtones
for the first time. In musical terms, the observations saw the
first two harmonics above the main tone.
"We do
see two more bumps and wiggles out there," Dr. Ruhl said.
"We can move to the question of, `What do these bumps and
wiggles tell us?' "
Dr. Max Tegmark,
a cosmologist at the University of Pennsylvania, said that while
the new results were still far from absolute proof of the inflation
theory, their agreement with the theory was uncanny and would
cast doubt on alternative models. "It's even scary that things
agree this well," he said. "This is a very bad day for
the competition."
Some other
scientists, including Dr. Andrew Lange of Caltech, a leader of
the Boomerang group, said the results strikingly showed that cosmologists
understood the composition and behavior of the universe in the
first few hundred thousand years of its life. It was then that
the sound waves were humming through the young cosmos; astronomers
believe the microwave background radiation was emitted as the
universe cooled below a critical temperature when it was about
400,000 years old.
"We've
really been waiting for the other shoe to drop," Dr. Lange
said in reference to the lengthy search for the overtones. "What
we're confirming for the first time is a very generic prediction
of modern cosmology."
Although astronomers
said much more detailed observations, including the discovery
of further overtones, would be required to define the quantum
fluctuations and to verify inflation, the results are likely to
be seen as major victories for two scientists in particular.
The first,
Dr. Alan Guth of the Massachusetts Institute of Technology, developed
the germ of the inflation model in 1980, a theory he has called
"the ultimate free lunch" because it shows how the entire
universe could have exploded out of nothing and impressed the
quantum fluctuations on the cosmos.
The results
also provide major support for ideas closely associated with Dr.
David Schramm, a Chicago cosmologist who died in a plane crash
late in 1997. Dr. Schramm and his colleagues worked out a theory,
unrelated to inflation, using trace elements created in the Big
Bang explosion to gauge the amount of ordinary matter in the universe.
Those values
agree closely with the amounts deduced from the intensity of the
sound wave overtones; that intensity is affected by the sloshing
of matter in the sound waves' peaks and troughs.
On the other
hand, the results also leave cosmologists with some deep and perhaps
troubling questions.
For example,
the new observations confirm that most of the cosmos seems to
be made of so-called dark matter and dark energy, possibly particles
or energy lurking somewhere in space but still never detected
directly. Dr. Turner, of Chicago, said skeptics might well term
that picture "the absurd universe, or the preposterous universe."
Sir Martin
Rees, an astrophysicist at Cambridge University, said scientists
were left with the question of whether fundamental physical laws
would someday explain that strange mixture of ingredients, or
whether the precise amounts were a sort of accident of how the
universe came into being — something like snowflakes, each
of which has a hexagonal symmetry but carries a pattern that is
otherwise unique.
"It may
well turn out that the underlying laws do not give us these numbers,
any more than they give the detailed pattern of a snowflake,"
Sir Martin said.
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