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arXiv · math-ph/9902013

Clifford Periodicity from Finite Groups

Luis J. Boya·Mark S. Byrd
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Abstract

We deduce the periodicity 8 for the type of $Pin$ and $Spin$ representations of the orthogonal groups $O(n)$ from simple combinatorial properties of the finite Clifford groups generated by the gamma matrices. We also include the case of arbitrary signature $O(p,q)$. The changes in the type of representation can be seen as a rotation in the complex plane. The essential result is that adding a $(+)$ dimension performs a rotation by $π/4$ in the counter clock-wise sense, but for each $(-)$ sign in the metric, the rotation is clockwise.

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Luis J. Boya, Mark S. Byrd. 1999-02-09. Clifford Periodicity from Finite Groups. https://arxiv.org/abs/math-ph/9902013

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