Notes on obstructions in the hyperbolic Clifford algebra bundle structure
Abstract
Starting from a general analysis of obstruction classes, we develop the investigation of obstructions associated with the bundle structure of the hyperbolic Clifford algebra. By taking into account particularities arising from the Whitney sum, it is shown that, unlike classical tangent bundle cases, the hyperbolic frame bundle of an oriented manifold admits lifting without any topological obstruction, that is, it admits a structure of the connected double covering of GL+(2m,ℝ), and the hyperbolic tangent bundle carries a Spinem,m structure (with m=dimℳ), whatever the value of w2(ℳ). These conclusions are known from the work of Karoubi and Gualtieri and the point of this note is that they follow from the Whitney product formula alone, or from the additivity formula of Whitney sums with an explicit covering group, without recourse to Karoubi's criterion for indefinite signature. We also describe the spinor bundles involved, which are bundles of differential forms and not Dirac spinor bundles and show that orientability is needed for the covering of the full linear group.
Related
- Spin-Clifford Bundles and Spin Connections on the Hyperbolic Clifford Algebra - Part I
- On the Geometric Structure of Hyperbolic Clifford Bundles and Associated Spin Groups
- Okubo algebras and Exceptional Periodicity: tetracode gradings, root-lattice obstructions and Clifford cones
- On the center of the Clifford Algebra
- Hybrid Clifford Codes via Operator Algebra Quantum Error Correction and Projective Representation Theory
BibTeX
@misc{silva2026notes,
title = {{Notes on obstructions in the hyperbolic Clifford algebra bundle structure}},
author = {J. M. Hoff da Silva and E. Notte-Cuello},
howpublished = {arXiv},
year = {2026},
month = nov,
doi = {10.48550/arxiv.2605.16558},
eprint = {2605.16558},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2605.16558},
}
RIS
TY - UNPB
TI - Notes on obstructions in the hyperbolic Clifford algebra bundle structure
AU - J. M. Hoff da Silva
AU - E. Notte-Cuello
PY - 2026
DA - 2026/11/03
PB - arXiv
DO - 10.48550/arxiv.2605.16558
UR - https://arxiv.org/abs/2605.16558
AB - Starting from a general analysis of obstruction classes, we develop the investigation of obstructions associated with the bundle structure of the hyperbolic Clifford algebra. By taking into account particularities arising from the Whitney sum, it is shown that, unlike classical tangent bundle cases, the hyperbolic frame bundle of an oriented manifold admits lifting without any topological obstruction, that is, it admits a structure of the connected double covering of GL^+(2m,ℝ), and the hyperbolic tangent bundle carries a Spin^e_m,m structure (with m=dimℳ), whatever the value of w_2(ℳ). These conclusions are known from the work of Karoubi and Gualtieri and the point of this note is that they follow from the Whitney product formula alone, or from the additivity formula of Whitney sums with an explicit covering group, without recourse to Karoubi's criterion for indefinite signature. We also describe the spinor bundles involved, which are bundles of differential forms and not Dirac spinor bundles and show that orientability is needed for the covering of the full linear group.
ER -