Monday, July 09, 2007

ALICE gets uk brain

As construction of the World`s largest machine, the Large Hadron Collider (LHC) at CERN in Geneva (Switzerland), gears up for completion next year, the four main experiments, that will study different aspects of the resulting high-energy particle collisions, are also gearing up. For one such experiment, called ALICE, this process got a step closer last week when a crucial part of the 10,000-ton detector, the British-built Central Trigger Processor (CTP), was installed in the ALICE cavern, some 150 feet underground.

The ALICE experiment will probe the mysteries surrounding the structure of matter. Head-on collisions of lead nuclei at the LHC will create sub-atomic sized fireballs with huge temperatures and densities and recreate the conditions that are believed to have existed less than a millionth of a second after an event commonly known as the Big Bang.

These 'mini Big Bangs' will produce temperatures of over a trillion degrees - 100,000 times hotter than the centre of the Sun – and neutrons and protons (which make up the nuclei of atoms) are expected to 'melt' into a new state of matter – quark-gluon plasma.

A quark-gluon plasma (QGP) is a phase of quantum chromodynamics (QCD) which exists at extremely high temperature and/or density. This phase consists of (almost) free quarks and gluons which are the basic building blocks of matter. QGP is believed to have existed during the first 20 to 30 microseconds after the universe came into existence in the process following a Big Bang.

Contrary to popular myth, ALICE is not likely to produce Black Holes, nor the singularities produced by matter in bulk.

ALICE, is the acronym for A Large Ion Collider Experiment, one of the largest experiments in the world devoted to research in the physics of matter at an infinitely small scale.

Scientists have found that everything in the Universe is made up from a small number of basic building blocks called elementary particles, governed by a few fundamental forces.

Some of these particles are stable and form the normal matter, the others live for fractions of a second and then decay to the stable ones. All of them would have coexisted for a few instants after the Big Bang.

Since then, only the enormous concentration of energy that can be reached in an accelerator at CERN can bring them back to life. Therefore, studying particle collisions is like "looking back in time", recreating the environment present at the origin of our Universe.

By studying particle collisions we hope to learn more about the force that holds atomic nuclei together (the strong force), the origin of the mass of nuclear matter and much, much more.

The most familiar basic force is gravity. It keeps our feet on the ground and the planets in motion around the Sun. On individual particles though, the effects of gravity are extremely small. Only when we have matter in bulk - as in ourselves or in planets - does gravity dominate.
Microscopic microstate blackholes at the LHC by Lubos @ the Reference Frame
The Quark Gluon Plasma paradox by Dorigo @ A Quantum Diaries Survivor
NASA scientists pioneer technique for 'weighing' black holes EurekAlert!

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