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arXiv · 1905.01366

Noncommutative cross-ratio and Schwarz derivative

Vladimir Retakh·Vladimir Rubtsov·Georgy Sharygin
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Abstract

We present here a theory of noncommutative cross-ratio, Schwarz derivative and their connections and relations to the operator cross-ratio. We apply the theory to "noncommutative elementary geometry" and relate it to noncommutative integrable systems. We also provide a noncommutative version of the celebrated "pentagramma mirificum".

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Vladimir Retakh, Vladimir Rubtsov, Georgy Sharygin. 2019-05-03. Noncommutative cross-ratio and Schwarz derivative. https://arxiv.org/abs/1905.01366

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