Non-reduction of relations in the Gromov space to Polish actions

Abstract

It is shown that, in the Gromov space of isometry classes of pointed proper metric spaces, the equivalence relations defined by existence of coarse quasi-isometries or being at finite Gromov-Hausdorff distance, cannot be reduced to the equivalence relation defined by any Polish action.

9 pages. To appear in Notre Dame J. Form. Log. A small correction was made. arXiv admin note: text overlap with arXiv:1209.0307

Cited by in corpus (1)

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