English

Pin Groups in General Relativity

High Energy Physics - Theory 2020-02-05 v3 General Relativity and Quantum Cosmology Mathematical Physics Differential Geometry math.MP

Abstract

There are eight possible Pin groups that can be used to describe the transformation behaviour of fermions under parity and time reversal. We show that only two of these are compatible with general relativity, in the sense that the configuration space of fermions coupled to gravity transforms appropriately under the space-time diffeomorphism group.

Cite

@article{arxiv.1709.02742,
  title  = {Pin Groups in General Relativity},
  author = {Bas Janssens},
  journal= {arXiv preprint arXiv:1709.02742},
  year   = {2020}
}

Comments

9 pages, added section 7 on the role of diffeomorphism invariance

R2 v1 2026-06-22T21:37:23.456Z