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- Pennsylvania State UniversityUS63 papers
- University of PisaIT58 papers
- Texas A&M UniversityUS34 papers
- University of BolognaIT33 papers
- Duke UniversityUS31 papers
- Nanjing UniversityCN29 papers
- National Research CouncilLK25 papers
- University of WashingtonUS25 papers
- Centre National de la Recherche ScientifiqueFR23 papers
- Princeton UniversityUS23 papers
- Tel Aviv UniversityIL23 papers
- Pontificia Universidad Católica de ChileCL22 papers
6 papers · 2 filters
Abelian group actions and hypersmooth equivalence relations
Michael R. Cotton
We show that a Borel action of a standard Borel group which is isomorphic to a sum of a countable abelian group with a countable sum of real lines and circles induces an orbit equi…
On Polish groups admitting non-essentially countable actions
Alexander S. Kechris, Maciej Malicki, Aristotelis Panagiotopoulos +1
It is a long-standing open question whether every Polish group that is not locally compact admits a Borel action on a standard Borel space whose associated orbit equivalence relati…
On Extensions of Partial Isomorphisms
Mahmood Etedadialiabadi, Su Gao
In this paper we study a notion of HL-extension (HL standing for Herwig--Lascar) for a structure in a finite relational language . We give a description of all finite…
Bounds on Scott Ranks of Some Polish Metric Spaces
William Chan
If is a proper Polish metric space and is any countable dense submetric space of , then the Scott rank of in the natural firs…
The Complexity of the Classification Problems of Finite-Dimensional Continua
Cheng Chang, Su Gao
We consider the homeomorphic classification of finite-dimensional continua as well as several related equivalence relations. We show that, when , the classification probl…
Cardinality of Wellordered Disjoint Unions of Quotients of Smooth Equivalence Relations
William Chan, Stephen Jackson
Assume . Let denote the relation of being in bijection. Let and be a se…