The conjecture that essentially countable subrelations of abelian Polish-group orbit relations are essentially hyperfinite
The conjecture that essentially countable subrelations of abelian Polish-group orbit relations are essentially hyperfinite
Let be an abelian Polish group, and let be an orbit equivalence relation induced by a Borel action of on a Polish space. Let be a Borel equivalence relation, and write when is Borel reducible to . An equivalence relation is essentially countable if it is Borel reducible to a countable Borel equivalence relation, and essentially hyperfinite if it is Borel reducible to a hyperfinite Borel equivalence relation.
Essential hyperfiniteness conjecture. If
and is essentially countable, then is essentially hyperfinite.
The statement generalizes the paper's theorem that this conclusion holds in a special case. Its general validity is presented as an open conjecture.
Sources & referencesView supporting material
Primary source
Longyun Ding and Su Gao, “Non-Archimedean Abelian Polish Groups and Their Actions”, arXiv:1512.07677 (2015).
Progress summary
Nothing recorded yet. Refresh searches the literature and the public web for attempts on this problem, and writes the first summary here.
Solutions 0
Sign in to submit a solution.
No solutions have been posted yet.