Universe's first seconds unveiled

'Little bang' experiment helps physicists understand crucial moments after the 'big bang.'

An international group of physicists has reenacted in miniature the birth of the material universe.

Their so-called "little bang" experiments re-created conditions thought to prevail just 10 millionths of a second after our universe appeared in a "big bang" explosion of pure energy. The experiments, reported today, created a new state of matter never seen by physicists before.

It is the kind of matter big-bang theory says first emerged from the primordial energy. Then, like steam forming water drops, it condensed into the familiar forms of matter.

This is "an important step forward in the understanding of the early evolution of the universe," says Luciano Maiani, director general of the European Center for Particle Physics (CERN) in Geneva, where the experiments took place.

Physicists had been able to backtrack cosmic evolution to within three minutes after the big bang using laboratory-tested theory. That time is when the familiar matter that makes up atomic nuclei appeared. Current theory of what happened before that was unverified. Now that theory has been laboratory tested to within 10 microseconds after the show began 12 to 14 billion years ago.

Cosmologist John Bahcall of the Institute for Advanced Study in Princeton, N.J., calls it "a fantastic achievement." He adds, "It will make a laboratory experiment out of what was theology."

Scientists from 26 countries joined in seven key experiments carried out at CERN over the past six years. It has been an odyssey of discovery into an uncharted region populated with strange entities bearing the whimsical names physicists often give their concepts.

The explorers went in search of what until now was considered a mythical beast called a quark-gluon state of matter.

Standard particle theory said it might exist. Theory also said researchers might never find it. Quarks - a term co-opted from James Joyce - underlie nuclear matter. They make up the protons and neutrons that, in turn, make up an atomic nucleus.

Gluons are force-related particles that stick the quarks together. However, theory predicted and, until now, experiment confirmed, that gluons bind the quarks so tightly that quarks could not be pried out of their proton and neutron cages. Yet theory also predicted that the first matter to form from big-bang energy would be a primordial soup of free-swimming quarks and gluons.

It would take very hot, very dense energy to brew up that soup. CERN's accelerators smashed lead nuclei into other lead nuclei and lead nuclei into gold nuclei to do it. This produced conditions 100,000 times hotter than the center of the sun and energy densities 20 times greater than those in ordinary atomic nuclei.

Looking at what came flying out of those conditions in seven different ways, the experimenters conclude that the mythical beast is mythical no more.

No one of the seven kinds of measurement is conclusive. Taken together, they form a body of circumstantial evidence that CERN calls "compelling enough to say that we have formed a new state of matter."

CERN's Dr. Maiani explains that these experiments have opened "an entirely new territory to be explored" in studying this quark-gluon matter. CERN can't pursue this until a more powerful accelerator begins operation in 2005. A heavy-nuclei collider at Brookhaven National Laboratory at Upton, N.Y., now will take up the chase.

Meanwhile, Dr. Bahcall says, "Physicists will jump up and down with joy."

(c) Copyright 2000. The Christian Science Publishing Society

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