Critical behavior of the Schwinger model with Wilson fermions

Abstract

We present a detailed analysis, in the framework of the MFA approach, of the critical behaviour of the lattice Schwinger model with Wilson fermions on lattices up to 24 2 , through the study of the Lee-Yang zeros and the specific heat. We find compelling evidence for a critical line ending at κ = 0.25 at large β. Finite size scaling analysis on lattices 8 2 , 12 2 , 16 2 , 20 2 and 24 2 indicates a continuous transition. The hyperscaling relation is verified in the explored β region.

The phase diagrams of the schwinger and gross-neveu models with Wilson fermions

“…Using Lee-Yang zeroes, finite-size scaling and other techniques the results of [2] support the free boson scenario, where the model lies in the same universality class as the Ising model, with critical exponents ν = 1, α = 0. This is not in agreement with [3] where finite-size scal- * Supported by EU TMR Project No. ERBFMBI-CT96-1757 and a Forbairt European Presidency Post Doctoral Fellowship.…”

Grassmann tensor renormalization group approach to one-flavor lattice Schwinger model

“…One may naively expect that a phase transition line runs from β ¼ 0.0 to ∞ belonging to the 2D Ising universality class. A result obtained by the microcanonical fermionic average approach, however, indicates that the phase transition at finite β lies in a different universality class from the 2D Ising model [4]. Furthermore, an analysis of the weak coupling expansion on large lattices disproves even the existence of the phase transition line [5].…”

Baryonic thermal fluctuations in finite temperature QCD

“…However it could be negative and in fact this unpleasant situation has been found for some gauge configurations in numerical simulations of the Schwinger model done in the unphysical strong coupling region [15]. However the unitary character of the gauge group implies that all the eigenvalues are upper bounded by the relation |λ| ≤ 8…”