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arXiv · 0901.0880

A new characterization of Conrad's property for group orderings, with applications

Adam Clay·Andrés Navas·Cristóbal Rivas
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Abstract

We provide a pure algebraic version of the dynamical characterization of Conrad's property. This approach allows dealing with general group actions on totally ordered spaces. As an application, we give a new and somehow constructive proof of a theorem first established by Linnell: an orderable group having infinitely many orderings has uncountably many. This proof is achieved by extending to uncountable orderable groups a result about orderings which may be approximated by their conjugates. This last result is illustrated by an example of an exotic ordering on the free group given in the Appendix.

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Adam Clay, Andrés Navas, Cristóbal Rivas. 2009-01-18. A new characterization of Conrad's property for group orderings, with applications. https://doi.org/10.2140/agt.2009.9.2079

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