Logic Seminar

This talk presents an extension of the theory of turbulent
Polish group actions introduced by Hjorth to certain classes of equivalence
relations that cannot be induced by Polish group actions. The main
reason for this extension is to analyze the complexity and dynamical
structure of the ''quasi-isometry'' and ''finite
Gromov-Hausdorff distance'' relations in the Gromov space of isometry
classes of pointed proper metric spaces. This analysis is in turn
motivated by questions pertaining to the generic geometry of orbits of
general dynamical systems.

This is joint work with Jesus A. Alvarez Lopez (USC-Spain).