Phase Transitions in Relativistic Systems

Abstract

The BCS free energy for 3P₂ paired neutron matter is derived taking account of relativistic effects. It is found that the values taken by the Ginzburg-Landau parameters are always in the region of the phase diagram correponding to a unitary phase.

Phase transitions in the early universe are also discussed with inclusion of the effects of Higgs scalar chemical potentials as well as fermionic chemical potentials. The conditions for equilibrium, and the critical density to prevent symmetry restoration at high temperatures are studied. It is observed that the decay of pre-existing Higgs scalar asymmetries could greatly reduce baryon number and lepton number to entropy ratios from their initial values.

Phase transitions in supersymmetric theories and the phenomenom of symmetry anti-restoration in a supersymmetric model with a U(1) gauge symmetry are studied at finite density.