General
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Written by Daniel
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Tuesday, 17 August 2010 16:51 |
From ARS Technica
Quantum chromodynamics (QCD), the theory that describes the strong nuclear force, is odd even by quantum mechanical standards. QCD dictates that, unlike pretty much any other particle, when you pull apart two quarks—the constituent particles of hadrons and one of the base particles of QCD—the energy between them does not decrease. Instead, it increases, a property known as confinement. This means that if you pulled hard enough on two bound quarks, the energy between them could become so great that it would cause a quark-antiquark pair to pop into existence and alleviate the strain.
Quark-antiquark pairs are also thought to be a major component of the vacuum that pervades our Universe. Instead of being empty, the vacuum is thought to be teeming with a complex mix of these fundamental particles. However, a new paper suggests that this view of the Universe may have things wrong.
QCD is also an oddity in that, at higher and higher energies, the interactions between its constituent particles becomes weaker and weaker, a phenomenon known as asymptotic freedom. Given the (proven) existence of asymptotic freedom, physicists can directly model QCD at high energies.....[More....] [Comments...]
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