Global gravitational anomalies

Edward Witten

Research output: Contribution to journalArticlepeer-review

236 Scopus citations

Abstract

A general formula for global gauge and gravitational anomalies is derived. It is used to show that the anomaly free supergravity and superstring theories in ten dimensions are all free of global anomalies that might have ruined their consistency. However, it is shown that global anomalies lead to some restrictions on allowed compactifications of these theories. For example, in the case of O(32) superstring theory, it is shown that a global anomaly related to π7(O(32)) leads to a Dirac-like quantization condition for the field strength of the antisymmetric tensor field. Related to global anomalies is the question of the number of fermion zero modes in an instanton field. It is argued that the relevant gravitational instantons are exotic spheres. It is shown that the number of fermion zero modes in an instanton field is always even in ten dimensional supergravity.

Original languageEnglish (US)
Pages (from-to)197-229
Number of pages33
JournalCommunications In Mathematical Physics
Volume100
Issue number2
DOIs
StatePublished - Jun 1985

All Science Journal Classification (ASJC) codes

  • Statistical and Nonlinear Physics
  • Mathematical Physics

Fingerprint

Dive into the research topics of 'Global gravitational anomalies'. Together they form a unique fingerprint.

Cite this