Fiorenzo Bastianelli — Page 5

arXiv1991

A Novel Chiral Boson

We introduce a new model describing a bosonic system with chiral properties. It consists of a free boson with two peculiar couplings to the background geometry which generalizes the Feigen-Fuchs-Dotsenko-Fateev construction. By choosing the two background charges of the model, it is possible to achieve any prefixed value of the left and right central charges and, in particular, obtain chiral bosonization. A supersymmetric version of the model is also given. We use the latter to identify the effective action induced by chiral superconformal matter.

hep-th↗

arXiv1991

The Path Integral for a Particle in Curved Spaces and Weyl Anomalies

The computation of anomalies in quantum field theory may be carried out by evaluating path integral Jacobians, as first shown by Fujikawa. The evaluation of these Jacobians can be cast in the form of a quantum mechanical problem, whose solution has a path integral representation. For the case of Weyl anomalies, also called trace anomalies, one is immediately led to study the path integral for a particle moving in curved spaces. We analyze the latter in a manifestly covariant way and by making use of ghost fields. The introduction of the ghost fields allows us to represent the path integral measure in a form suitable for performing the perturbative expansion. We employ our method to compute the Hamiltonian associated with the evolution kernel given by the path integral with fixed boundary conditions, and use this result to evaluate the trace needed in field theoretic computation of Weyl anomalies in two dimensions.

hep-th↗