2003/03/31 by N. Tetradis · 3 citations
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-lat #hep-ph #hep-th #nucl-th
paper · pdf · doi:10.1016/s0375-9474(03)01624-5
published as Nucl.Phys. A726 (2003) 93-119 · 29 pages, 9 figures, minor corrections, added references
arxiv created 2003/07/02 · openalex publication_date 2003/08/01 · arxiv updated 2010/04/05 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We study the qualitative features of the QCD phase diagram in the context of the linear quark-meson model with two flavours, using the exact renormalization group. We identify the universality classes of the second-order phase transitions and calculate critical exponents. In the absence of explicit chiral-symmetry breaking through the current quark masses, we discuss in detail the tricritical point and demonstrate that it is linked to the Gaussian fixed point. In its vicinity we study the universal crossover between the Gaussian and O(4) fixed points, and the weak first-order phase transitions. In the presence of explicit chiral-symmetry breaking, we study in detail the critical endpoint of the line of first-order phase transitions. We demonstrate the decoupling of pion fluctuations and identify the Ising universality class as the relevant one for the second-order phase transition.