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arXiv · 2107.07415

From forbidden configurations to a classification of some axial algebras of Monster type

Justin McInroy·Sergey Shpectorov
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Abstract

Ivanov introduced the shape of a Majorana algebra as a record of the $2$-generated subalgebras arising in that algebra. As a broad generalisation of this concept and to free it from the ambient algebra, we introduce the concept of an axet and shapes on an axet. A shape can be viewed as an algebra version of a group amalgam. Just like an amalgam, a shape leads to a unique algebra completion which may be non-trivial or it may collapse. Then for a natural family of shapes of generalised Monster type we classify all completion algebras and discover that a great majority of them collapse, confirming the observations made in an earlier paper.

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Justin McInroy, Sergey Shpectorov. 2021-07-15. From forbidden configurations to a classification of some axial algebras of Monster type. https://arxiv.org/abs/2107.07415

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