Constraints on the topology of Type IIB string theory

Kazuya Yonekura

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arXiv · 2403.04127

Constraints on the topology of Type IIB string theory

Kazuya Yonekura

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Abstract

We discuss some topological constraints on Type IIB string theory that cannot be described by elementary characteristic classes. Anomaly cancellation of the worldvolume theory of a D3-brane requires a shifted Dirac quantization condition of the Ramond-Ramond 5-form flux. However, the required shift is sometimes inconsistent depending on the topology of spacetime backgrounds. The obstruction to the existence of a shifted quantization is described by a degree-6 cohomology class whose definition involves spin structure of spacetime manifolds. The cohomology class is interpreted as a background D3-charge, and the Gauss law constraint requires inclusion of additional D3-branes to cancel it.

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Kazuya Yonekura. 2024-03-07. Constraints on the topology of Type IIB string theory. https://arxiv.org/abs/2403.04127

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