Descriptive Set Theory Working Seminar - Fall 2026

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Time: Wednesdays 4-5pm
Location: 740 Evans Hall
Topic: Countable groups and their actions, CBERs, Borel graph combinatorics, and related topics

Tentative schedule:

• Sep 2: Andrew Marks - Coarse geometry of CBERs and Kaimanoivch's theorem
• Sep 9: Andrew Marks - Kaimanovich's theorem and separation index growth
• Sep 16: Felix Weilacher - Hyperfiniteness, asymptotic separation index 1, and Ozawa's result on subexponential growth and property A
• Sep 23:
• Sep 30:
• Oct 7: Koichi Oyakawa - the action of every hyperbolic group on its Gromov boundary is hyperfinite.
• Oct 14: MohammedSaid Alhalimi - The ergodic decomposition theorem
• Oct 21: MohammedSaid Alhalimi - The ergodic decomposition theorem
• Oct 28: No seminar
• Nov 4: Gabor Kun
• Nov 11: No seminar
• Nov 18:
• Nov 25: No seminar
• Dec 2: Su Gao