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arXiv · 2007.13884

On diffeomorphisms of even-dimensional discs

Alexander Kupers·Oscar Randal-Williams
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Abstract

We determine $\pi_*(BDiff_\partial(D^{2n})) \otimes \mathbb{Q}$ for $2n \geq 6$ completely in degrees $* \leq 4n-10$, far beyond the pseudoisotopy stable range. Furthermore, above these degrees we discover a systematic structure in these homotopy groups: we determine them outside of certain "bands" of degrees.

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Alexander Kupers, Oscar Randal-Williams. 2020-07-27. On diffeomorphisms of even-dimensional discs. https://arxiv.org/abs/2007.13884

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