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Pica, Claudio

Publications and source records attributed to Pica, Claudio.

S parameter at nonzero temperature and chemical potential

We compute the finite-temperature and matter density corrections to the S-parameter at the one-loop level. At nonzero temperature T and matter density {mu} Lorentz symmetry breaks and therefore we suggest a suitable generalization of the S-parameter. By computing the plasma correction, we discover a reduction of the S-parameter in the physically relevant region of small external momenta for any nonzero {mu} and T. In particular, the S-parameter vanishes at small m/T, where m is the mass of the fermions, due to the finite extent of the temporal direction. Our results are directly applicable to the determination of the S-parameter via first-principle lattice simulations performed with antiperiodic boundary conditions in the temporal direction.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Beta function and anomalous dimensions

We demonstrate that it is possible to determine the coefficients of an all-orders beta-function linear in the anomalous dimensions using as data the 2-loop coefficients together with the first one of the anomalous dimensions which are universal. The beta function allows us to determine the anomalous dimension of the fermion masses at the infrared fixed point, and the resulting values compare well with the lattice determinations.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Dual of QCD with one adjoint fermion

We construct the magnetic dual of QCD with one adjoint Weyl fermion. The dual is a consistent solution of the 't Hooft anomaly matching conditions, allows for flavor decoupling, and remarkably constitutes the first nonsupersymmetric dual valid for any number of colors. The dual allows to bound the anomalous dimension of the Dirac fermion mass operator to be less than one in the conformal window.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗