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arXiv · 2301.07590

On order units in the augmentation ideal

Abstract

We study order units in the real group ring and the augmentation ideal, as well as in matrix algebras. We identify an infinite family of order units in the powers of the augmentation ideal, that includes the Laplacian, and show that these order units are naturally obtained via cohomological operations from more simpler diagonal order units in matrix algebras.

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Piotr Mizerka, Piotr W. Nowak. 2023-01-18. On order units in the augmentation ideal. https://arxiv.org/abs/2301.07590

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