Schwarz-Sen duality made fully local

TL;DR

This paper develops a fully local duality symmetric electromagnetic action by introducing a space-time dependent mixing angle, leading to Maxwell-like equations with generalized gauge invariance.

Contribution

It generalizes the Schwarz-Sen duality symmetric action to include a space-time dependent mixing angle between electric and magnetic fields.

Findings

The generalized action exhibits full symmetry of the electromagnetic stress tensor.

Rotated fields satisfy Maxwell-like equations with a space-time dependent mixing angle.

A new gauge invariance for the generalized action is established.

Abstract

Duality symmetric electromagnetic action a la Schwarz-Sen is shown to appear naturally in a chain of equivalent actions which interchange equations of motion with Bianchi identities. Full symmetry of the electromagnetic stress tensor is exploited by generalizing this duality symmetric action to allow for a space-time dependent mixing angle between electric and magnetic fields. The rotated fields are shown to satisfy Maxwell-like equations which involve the mixing angle as a parameter, and a generalized gauge invariance of the new action is established.