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arXiv · 1310.3210

Euclidean-valued group cohomology is always reduced

Tim Austin
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Abstract

If G is a countable discrete group acting linearly on a finite-dimensional vector space over any topological field, then the groups of coboundaries are closed for the product topology in all degrees, and hence the cohomology is reduced in all degrees. This is deduced from a more general automatic-closure theorem for continuous linear transformations between inverse limits of finite-dimensional vector spaces.

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Tim Austin. 2017-02-16. Euclidean-valued group cohomology is always reduced. https://doi.org/10.1142/s1793525318500243

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