Chern-Simons-like action induced radiatively in General Relativity

TL;DR

This paper calculates the radiative induction of a Chern-Simons-like gravitational action in four-dimensional spacetime through one-loop fermionic corrections, highlighting parity violation effects in a weak field regime.

Contribution

It provides an explicit one-loop calculation of the Chern-Simons-like gravitational term induced by fermions in a four-dimensional setting, including parity-violating interactions.

Findings

Explicit form of the induced Chern-Simons-like action

Role of parity violation in gravitational corrections

Application of dimensional regularization in gravitational context

Abstract

The Chern-Simons-like gravitational action is evaluated explicitly in four dimensional space-time by radiative corrections at one-loop level. The calculation is performed in fermionic sector where the Dirac fermions interact with the background gravitational field, including the parity-violating term \bar\psi \bs\gamma_5\psi. The investigation takes into account the weak field approximation and dimensional regularization scheme.