On limits of betweenness relations

David Bradley-Williams; John K Truss

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arXiv · 2108.12904

On limits of betweenness relations

David Bradley-Williams·John K Truss

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Abstract

We give a flexible method for constructing a wide variety of limits of betweenness relations. This unifies work of Adeleke, who constructed a Jordan group preserving a limit of betweenness relations, and Bhattacharjee and Macpherson who gave an alternative method using a Fra\"ss\'e-type construction. A key ingredient in their work is the notion of a tree of B-sets. We employ this, and extend its use to a wider class of examples.

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David Bradley-Williams, John K Truss. 2021-08-29. On limits of betweenness relations. https://arxiv.org/abs/2108.12904

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