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arXiv · 2312.01106

The Chern character of $\vartheta$-summable $\mathcal{C}_q$-Fredholm modules over locally convex differential graded algebras

Jonas Miehe
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Abstract

Let $\Omega$ be a locally convex differential graded algebra. We introduce the Chern character of $\vartheta$-summable $\mathcal{C}_q$-Fredholm modules over $\Omega$, generalizing the JLO cocycle to the differential graded setting. This allows treating the case of even $\vartheta$-summable Fredholm modules over $\Omega$ (which has been previously considered by G\"uneysu/Ludewig in the context of localization on loop spaces) and odd $\vartheta$-summable Fredholm modules over $\Omega$ simultaneously. We prove all naturally expected properties of this construction and relate it to the spectral flow in the odd case.

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Jonas Miehe. 2023-12-02. The Chern character of $\vartheta$-summable $\mathcal{C}_q$-Fredholm modules over locally convex differential graded algebras. https://arxiv.org/abs/2312.01106

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