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arXiv · 2202.09919

Line Bundle Twists for Unitary Bordism are Ghosts

Thorsten Hertl
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Abstract

We prove that the canonical twist $\zeta \colon K(\mathbb{Z},3) \rightarrow BGL_1(MSpin^c)$ does not extend to a twist for unitary bordism by showing that every continuous map $f \colon K(\mathbb{Z},3) \rightarrow BGL_1(MU)$ loops to a null homotopic map.

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Thorsten Hertl. 2022-02-20. Line Bundle Twists for Unitary Bordism are Ghosts. https://doi.org/10.2140/agt.2025.25.2053

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