Dynamical symmetry breaking in \(\text{QED}_3\) from the Wilson RG point of view (Q2774349)

The paper's subject is the dynamical chiral symmetry breaking. The authors show how it works in the large-\(N\) Gross-Neven model as the simplest example. In the rest of the paper, they focus on the QED in \((2+1)\) dimensions, or \(\text{QED}_3\). The effective Lagrangian is written, the RG equations for couplings are solved and the fixed points obtained. It seems that there appears a phase boundary and the chiral symmetry is broken. A gauge-independent calculation was performed that led to similar results. The RG flow diagrams look different for the number of flavours \(N\) above and below some critical value \(N_{\text{cr}}\). For \(N>N_{\text{cr}}\), the chiral symmetry was found to be broken irrespective of the gauge coupling, while the critical gauge coupling dividing into chirally broken and unbroken phases was found to exist for \(N<N_{\text{cr}}\).