arXiv subjects

A. Penna-Firme

Publications and source records attributed to A. Penna-Firme.

3 recordsLinked to original sources

arXiv2000

Conformal symmetry, anomaly and effective action for metric-scalar gravity with torsion

We consider some aspects of conformal symmetry in a metric-scalar-torsion system. It is shown that, for some special choice of the action, torsion acts as a compensating field and the full theory is conformally equivalent to General Relativity on classical level. Due to the introduction of torsion, this equivalence can be provided for the positively-defined gravitational and scalar actions. One-loop divergences arising from the scalar loop are calculated and both the consequent anomaly and the anomaly-induced effective action are derived.

gr-qc↗

arXiv1999

Scalar QED $\hbar$-Corrections to the Coulomb Potential

The leading long-distance 1-loop quantum corrections to the Coulomb potential are derived for scalar QED and their gauge-independence is explicitly checked. The potential is obtained from the direct calculation of the 2-particle scattering amplitude, taking into account all relevant 1-loop diagrams. Our investigation should be regarded as a first step towards the same programme for effective Quantum Gravity. In particular, with our calculation in the framework of scalar QED, we are able to demonstrate the incompleteness of some previous studies concerning the Quantum Gravity counterpart.

hep-th↗

arXiv1998

Anti-symmetric Tensor Matter Fields and Non-Linear Sigma-Model

The equivalence between rank-2 anti-symmetric tensor fields, considered as gauge potentials, and torsionless non-linear $σ$-models suggests us to study the possibility of coupling tensorial matter with Yang-Mills fields, through the gauging of the isometries of the target space. We show that this coupling is actually possible; however, the matter appears no longer as an elementary field, but rather as a composite one, expressed in terms of the bosonic degrees of freedom of the $σ$-model. A possible phenomenological application is presented that describes the interactions among vector mesons in terms of the geometrical properties of the target manifold. Also, spin-2 meson resonances may naturally be accommodated whenever the $σ$-model's target manifold is non-symmetric.

hep-th↗