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arXiv · 1701.01314

Classification of plethories in characteristic zero

Magnus Carlson
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Abstract

We classify plethories over fields of characteristic zero, thus answering a question of Borger-Wieland and Bergman-Hausknecht. All plethories over characteristic zero fields are linear, in the sense that they are free plethories on a bialgebra. For the proof we need some facts from the theory of ring schemes where we extend previously known results. We also classify plethories with trivial Verschiebung over a perfect field of non-zero characteristic and indicate future work.

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Magnus Carlson. 2017-01-05. Classification of plethories in characteristic zero. https://arxiv.org/abs/1701.01314

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