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arXiv · 2501.17730

The rational Gurarii space and its linear isometry group

Ondřej Kurka·Maciej Malicki
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Abstract

We show that the classes of partial isometries in finite-dimensional polyhedral spaces and in finite-dimensional rational polyhedral spaces do not have the weak amalgamation property. This implies that the linear isometry group of the rational Gurarii space does not have a comeager conjugacy class. Our methods demonstrate also that the classes of finite-dimensional polyhedral spaces and of finite-dimensional rational polyhedral spaces fail to have the Hrushovski property.

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Ondřej Kurka, Maciej Malicki. 2025-01-29. The rational Gurarii space and its linear isometry group. https://doi.org/10.4064/sm250501-5-12

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