PHASES OF QCD FROM SMALL TO LARGE Nf: (SOME) LATTICE RESULTS

We analyze the phases of strong interactions in the space of the flavor number Nf, bare coupling gL, and temperature T by lattice MonteCarlo simulations for two and three unrooted staggered flavors, corresponding to eight and twelve continuum flavors, respectively. We observe a Coulomb-like phase at intermediate lattice couplings which we interpret as the avatar of a continuum conformal theory for Nf = 12. We comment on the possible occurrence of an UVFP associated with the bulk phase transition between the strong coupling lattice phase and the Coulomb-like phase.

VANISHING OF THE BARE COUPLING IN FOUR DIMENSIONS

We examine two restructurings of the series relationship between the bare and renormalized coupling constant in dimensional regularization. In one of these restructurings, we are able to demonstrate via all-orders summation of leading and successive ∊ = 0 (dimensionality = 4) poles that the bare coupling vanishes in the dimension-4 limit.

INTEGRABLE PERTURBATIONS OF CFT WITH COMPLEX PARAMETER: THE M3/5 MODEL AND ITS GENERALIZATIONS

By using the thermodynamic Bethe ansatz approach, we give evidence of the existence of both massive and massless behaviors for the ϕ2,1 perturbation of the M3,5 nonunitary minimal model, thus resolving apparent contradictions in the previous literature. The two behaviors correspond to changing the perturbing bare coupling constant from real values to imaginary ones. Generalizations of this picture to the whole class of nonunitary minimal models Mp,2p±1, perturbed by their least relevant operator, lead to a cascade of flows similar to that of unitary minimal models perturbed by ϕ1,3. Various aspects and generalizations of this phenomenon and the links with the Izergin–Korepin model are discussed.