Phase transitions between confinement and higgs phases in ${\cal N}=1\,\, SU(N_c)$ SQCD with $1\leq N_F\leq N_c-1$ quark flavors

Abstract

Considered is 4-dimensional ${\cal N}=1$ supersymmetric $SU(N_c)$ QCD (SQCD) with $1\leq N_F\leq N_c-1$ equal mass quark flavors in the fundamental representation. The gauge invariant order parameter $\rho$ is introduced distinguishing confinement (with $\rho=0$) and higgs (with $\rho\neq 0$) phases. Using a number of independent arguments for different variants of transition between the confinement and higgs regimes, it is shown that transitions between these regimes are not crossovers but the phase transitions. Besides, it is argued that these phase transitions are of the first order. This is opposite to the conclusion of the paper of E. Fradkin and S.H. Shenker [10] that the transition between the confinement and higgs regimes is the crossover, not the phase transition. And although the theories considered in this paper and in [10] are different, an experience shows that there is a widely spread opinion that the conclusion of [10] is applicable to all QCD-like theories: both lattice and continuum, both not supersymmetric and supersymmetric. This opinion is in contradiction with the results of this paper.