DOI: 10.1140/epjc/s2003-01220-7
Phase transition between three- and two-flavor QCD?
C. WetterichInstitut für Theoretische Physik, Universität Heidelberg, Philosophenweg 16, 69120 Heidelberg, Germany C.Wetterich@thphys.uni-heidelberg.de
(Received: 12 March 2001 / Revised version: 2 April 2003 / Published online: 2 June 2003)
Abstract
We explore the possibility that QCD may undergo a phase transition
as a function of the strange quark mass. This would hint towards
models with "spontaneous color symmetry breaking" in the
vacuum. For two light quark flavors we
classify possible colored
quark-antiquark, diquark and gluon condensates that are compatible
with a spectrum of integer charged states and conserved
isospin and baryon number. The "quark mass phase transition"
would be linked to an unusual realization
of baryon number in QCD
2 and could be tested
in lattice simulations. We emphasize, however, that at the
present stage the Higgs picture of the vacuum cannot predict
a
quark mass phase transition - a smooth crossover remains as
a
realistic alternative. Implications of the Higgs picture for
the high-density phase transition in QCD
2 suggest
that this transition is characterized by the
spontaneous breaking of isospin for nuclear and quark matter.
© Società Italiana di Fisica, Springer-Verlag 2003
