Naslov
Axial gravity, massless fermions and trace anomalies

Autori
Bonora, Loriano ; Cvitan, Maro ; Dominis Prester, Predrag ; Duarte Pereira, Antonio ; Giaccari, Stefano ; Štemberga, Tamara

Izvornik
European physical journal C : particles and fields (1434-6044) 77 (2017), 8; 511-1

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
trace anomaly, Pontryagin density, massless fermions

Sažetak
This article deals with two main topics. One is odd parity trace anomalies in Weyl fermion theories in a 4d curved background, the second is the introduction of axial gravity. The motivation for reconsidering the former is to clarify the theoretical background underlying the approach and complete the calculation of the anomaly. The reference is in particular to the difference between Weyl and massless Majorana fermions and to the possible contributions from tadpole and seagull terms in the Feynman diagram approach. A first, basic, result of this paper is that a more thorough treatment, taking account of such additional terms and using dimensional regularization, confirms the earlier result. The introduction of an axial symmetric tensor besides the usual gravitational metric is instrumental to a different derivation of the same result using Dirac fermions, which are coupled not only to the usual metric but also to the additional axial tensor. The action of Majorana and Weyl fermions can be obtained in two different limits of such a general configuration. The results obtained in this way confirm the previously obtained ones.

Izvorni jezik
Engleski

Znanstvena područja
Fizika

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