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arXiv · 2509.24284

A Fourier-Mukai Transform For KR Theory

Abstract

In complex K-theory, the Fourier-Mukai transform is an isomorphism between K-theory groups of a torus and its dual torus which is defined by pullback, tensoring by the Poincaré line bundle and pushforward. The Fourier-Mukai transform extends to families of dual tori provided one works with twisted K-theory. The Fourier-Mukai transform is then an isomorphism between twisted K-theory groups of $T$-dual torus bundles. In this paper we prove an extension of these results to twisted KR-theory. We introduce a notion of Real $T$-duality for torus bundles with Real structures and prove the existence of Real $T$-duals. We then define a Real Fourier-Mukai transform for Real $T$-dual torus bundles and prove that it is an isomorphism. Lastly, we consider an application of these results to the families index of Real Dirac operators which is relevant to Real Seiberg-Witten theory.

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BibTeXRIS

David Baraglia. 2025-09-29. A Fourier-Mukai Transform For KR Theory. https://arxiv.org/abs/2509.24284

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