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A TOPOMETRIC EFFROS THEOREM

Published online by Cambridge University Press:  02 February 2023

ITAÏ BEN YAACOV*
Affiliation:
INSTITUT CAMILLE JORDAN CNRS UMR 5208 UNIVERSITÉ CLAUDE BERNARD—LYON 1 43 BOULEVARD DU 11 NOVEMBRE 1918 69622 VILLEURBANNE, FRANCE E-mail: melleray@math.univ-lyon1.fr URL: http://math.univ-lyon1.fr/~begnac/ URL: http://math.univ-lyon1.fr/~melleray/
JULIEN MELLERAY
Affiliation:
INSTITUT CAMILLE JORDAN CNRS UMR 5208 UNIVERSITÉ CLAUDE BERNARD—LYON 1 43 BOULEVARD DU 11 NOVEMBRE 1918 69622 VILLEURBANNE, FRANCE E-mail: melleray@math.univ-lyon1.fr URL: http://math.univ-lyon1.fr/~begnac/ URL: http://math.univ-lyon1.fr/~melleray/

Abstract

Given a continuous and isometric action of a Polish group G on an adequate Polish topometric space $(X,\tau ,\rho )$ and $x \in X$ , we find a necessary and sufficient condition for $\overline {Gx}^{\rho }$ to be co-meagre; we also obtain a criterion that characterizes when such a point exists. This work completes a criterion established in earlier work of the authors.

Type
Article
Copyright
© The Author(s), 2023. Published by Cambridge University Press on behalf of The Association for Symbolic Logic

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References

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