Quantum phase transitions and new scales in QCD-like theories
  It is commonly believed that in confining vector-like gauge theories the center and chiral symmetry realizations are parametrically entangled, and if phase transitions occur, they must take place around the strong scale $\Lambda^{-1}$ of the gauge theory. We demonstrate that (non-thermal) vector-like theories formulated on ${\mathbb R}^{3} \times S^1$ where $S^1$ is a spatial circle exhibit new dynamical scales and new phenomena. There are chiral phase transitions taking place at $\Lambda^{-1}/N_c$ in the absence of any change in center symmetry. $\Lambda^{-1}/N_c$, invisible in (planar) perturbation theory, is also the scale where abelian versus non-abelian confinement regimes meet. Large $N_c$ volume independence (a working Eguchi-Kawai reduction) provides new insights and independently confirms the existence of these scales. We show that certain phases and scales are outside the reach of holographic (supergravity) modeling of QCD. 
Mithat Unsal