Spin^h structure, scalar and charged spinor eigenfunctions on the SU(3)/SO(3) Wu manifold


Gibson C., Günel O., Larios G., Pope C. N.

JOURNAL OF HIGH ENERGY PHYSICS, vol.2026, no.173, pp.1-53, 2026 (SCI-Expanded, Scopus)

  • Publication Type: Article / Article
  • Volume: 2026 Issue: 173
  • Publication Date: 2026
  • Doi Number: 10.1007/jhep05(2026)173
  • Journal Name: JOURNAL OF HIGH ENERGY PHYSICS
  • Journal Indexes: Scopus, Science Citation Index Expanded (SCI-EXPANDED), INSPEC, MathSciNet, zbMATH, Directory of Open Access Journals, Nature Index
  • Page Numbers: pp.1-53
  • Middle East Technical University Affiliated: No

Abstract

Generalised spin structures are necessary for placing fermions on manifolds that do not admit a standard spin structure. This is especially relevant in a dimensional reduction on such a manifold, which can then be compensated by using fermions that are appropriately charged under some Maxwell or Yang-Mills field defined on the internal manifold. A well known example in the physics literature is CP^2, which has four real dimensions and is the coset SU(3)/U(2). In this paper we focus on a five-dimensional coset space, namely the Wu manifold SU(3)/SO(3)max, where SO(3)max is maximal in SU(3). Intriguingly, the Wu manifold does not admit a spin structure or spinc structure, it does admit a spinh structure. We provide a physical interpretation of the spinh structure by considering spinors that are coupled to an SO(3) Yang-Mills field defined on the Wu manifold, but which carry half-integer “isospin,” thereby canceling the minus sign in the holonomy for uncharged spinors that provides the original obstruction to an ordinary spin structure. We also construct a gauge-covariantly constant spinor in the Wu manifold, and we show how this can be employed in order to construct spinh spinor harmonics from scalar harmonics. We provide a very explicit construction of all the scalar and spinh harmonics. In a follow-up paper, we shall employ the results we obtain here in order to discuss dimensional reductions and consistent reductions on the Wu manifold.