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Topological Z_{N+1} Charges on Fuzzy Sphere

Chuan-Tsung Chan·Chiang-Mei Chen·Hyun Seok Yang
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Abstract

We study the topological properties of fuzzy sphere. We show that the topological charge is only defined modulo N+1, that is finite integer quotient Z_{N+1}, where N is a cut-off spin of fuzzy sphere. This periodic structure on topological charges is shown based on the boson realizations of SU(2) algebra, Schwinger vs. Holstein-Primakoff. We argue that this result can have a natural K-theory interpretation and the topological charges on fuzzy sphere can be classified by the twisted K-theory. We also outline how solitons on fuzzy sphere can realize D-brane solitons in the presence of Neveu-Schwarz fivebranes proposed by Harvey and Moore.

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Chuan-Tsung Chan, Chiang-Mei Chen, Hyun Seok Yang. 2001-08-31. Topological Z_{N+1} Charges on Fuzzy Sphere. https://arxiv.org/abs/hep-th/0106269

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