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RIGHT after the big bang the Universe existed as a soup of free-roaming
fundamental particles that didn鈥檛 obey the normal rules of physics, scientists
have confirmed at CERN, the European laboratory for particle physics near
Geneva.

Particles such as protons and neutrons are actually made up of smaller
fundamental components called quarks which cannot exist on their own. Quarks are
kept tightly bound together by something called the strong force, which in turn
is mediated by other particles called gluons.

But theory predicts that immediately after the big bang, conditions would
have been so hot and dense that the strong force would break
down鈥攕queezing the quarks and gluons into a homogeneous soup. Only as the
Universe expanded and cooled, would the quarks undergo a 鈥減hase transition鈥� and
condense into complex particles.

Physicists at CERN put this idea to the test by smashing lead ions into each
other. This effectively re-enacted the big bang in miniature as energy released
by the collisions of the heavy ions created matter in an expanding fireball at
100 000 times the temperature of the centre of the Sun.

Seven teams worked backwards from signals measured in the experiments and
combined their data to recreate a point just microseconds after the big bang
itself. And they found compelling evidence that free quarks, unbound by the
strong force, are indeed created for a fleeting instant before being transformed
into normal matter. 鈥淭his creates a new architecture in the Universe,鈥� says CERN
spokesman Reinhard Stock.

Thomas Ludlam of Brookhaven National Laboratory in New York state agrees.
鈥淭his work tells us something fundamental about the nature and origin of matter
in our Universe,鈥� he says.