A note on D-branes in group manifolds: flux quantisation and D0-charge

TL;DR

This paper investigates D-branes in group manifolds, focusing on flux quantisation and D0-charge, revealing that D-branes are characterized by a gauge invariant two-form and proposing a new expression for D0 charge.

Contribution

It provides a gauge invariant characterization of D-branes in group manifolds and introduces a novel expression for D0 charge based on flux quantisation arguments.

Findings

D-branes are characterized by a gauge invariant two-form.

No evidence found for quantised U(1) gauge field flux.

Proposed a new expression for D0 charge of D-branes.

Abstract

We show that a D-brane in a group manifold given by a (twisted) conjugacy class is characterised by a gauge invariant two-form field determined in terms of the matrix of gluing conditions. Using a quantisation argument based on the path integral one obtains the known quantisation condition for the corresponding D-branes. We find no evidence for the existence of a quantised U(1) gauge field flux. We propose an expression for the D0 charge of such D-branes.