Anomalies and the Green-Schwarz Mechanism

TL;DR

This paper provides a pedagogical overview of spacetime anomalies in string theory, focusing on anomaly cancellation via the Green-Schwarz mechanism, anomaly inflow, and recent categorical reformulations.

Contribution

It offers a comprehensive review of anomaly cancellation methods in string theory, including the Green-Schwarz mechanism and anomaly inflow, with insights into recent categorical approaches.

Findings

Explanation of anomaly cancellation in type-I string theory

Review of anomaly inflow and D-brane couplings

Discussion of categorical reformulation of anomalies

Abstract

Anomalies are a very powerful tool in constraining theories beyond the standard model. We give a pedagogical overview of some topics illustrating the important role played by spacetime anomalies in string theory. After discussing the general problem of anomaly cancellation in quantum field theory, the focus is set on the cancellation of anomalies in type-I string theory through the Green-Schwarz mechanism. The notion of anomaly inflow is also reviewed, as well as its application to the evaluation of D-brane anomalous couplings. Finally, we briefly comment on recent developments concerning the reformulation of anomalies in the language of category theory.