Lie groups as permutation groups: Ulam's problem in the nilpotent case

Nicolas Monod

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arXiv · 2110.01650

Lie groups as permutation groups: Ulam's problem in the nilpotent case

Nicolas Monod

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Abstract

Ulam asked whether every connected Lie group can be represented on a countable structure. This is known in the linear case. We establish it for the first family of non-linear groups, namely in the nilpotent case. Further context is discussed to illustrate the relevance of nilpotent groups for Ulam's problem.

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Nicolas Monod. 2021-10-04. Lie groups as permutation groups: Ulam's problem in the nilpotent case. https://arxiv.org/abs/2110.01650

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