Obstructions to homotopy invariance of loop coproduct via parametrised fixed-point theory

Lea Kenigsberg; Noah Porcelli

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arXiv · 2407.13662

Obstructions to homotopy invariance of loop coproduct via parametrised fixed-point theory

Lea Kenigsberg·Noah Porcelli

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Abstract

Given $f: M \to N$ a homotopy equivalence of compact manifolds with boundary, we use a construction of Geoghegan and Nicas to define its Reidemeister trace $[T] \in \pi_1^{st}(\mathcal{L} N, N)$. We realize the Goresky-Hingston coproduct as a map of spectra, and show that the failure of $f$ to entwine the spectral coproducts can be characterized by Chas-Sullivan multiplication with $[T]$. In particular, when $f$ is a simple homotopy equivalence, the spectral coproducts of $M$ and $N$ agree.

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BibTeX RIS

Lea Kenigsberg, Noah Porcelli. 2024-07-18. Obstructions to homotopy invariance of loop coproduct via parametrised fixed-point theory. https://arxiv.org/abs/2407.13662

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