The first law of heterotic stringy black hole mechanics at zeroth order in alpha prime

Understand

We re-derive the first law of black hole mechanics in the context of the Heterotic Superstring effective action compactified on a torus to leading order in alpha prime, using Wald's formalism, covariant Lie derivatives and momentum maps.

• The Kalb-Ramond field strength of this theory has Abelian Chern-Simons terms which induce Nicolai-Townsend transformations of the Kalb-Ramond field.
• We show how to deal with all these gauge symmetries deriving the first law in terms of manifestly gauge-invariant quantities.
• In presence of Chern-Simons terms, several definitions of the conserved charges exist, but the formalism picks up only one of them to play a role in the first law.