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DTSTAMP:20251121T134858
DTSTART;TZID=America/Detroit:20260204T160000
DTEND;TZID=America/Detroit:20260204T170000
SUMMARY:Workshop / Seminar:On hypoellipticity of degenerate operators in testing and detection problems
DESCRIPTION:We study a class of degenerate diffusion generators that arise in sequential testing and quickest detection problems with partial information. The observation process is driven by k independent Brownian motions\, while the hidden state takes n+1 values with k<n. By moving to the posterior likelihood coordinates\, we analyze the Hömander's condition of the operator both without state switching (testing) and with switching (detection). We characterize the cases where the operator is hypoelliptic for the former\, give two different sufficient conditions for the latter\, and discuss their consequences.\n\nJoint work with Erhan Bayraktar
UID:142116-21890025@events.umich.edu
URL:https://events.umich.edu/event/142116
CLASS:PUBLIC
STATUS:CONFIRMED
CATEGORIES:Mathematics
LOCATION:East Hall - 1360
CONTACT:
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DTSTAMP:20260131T210649
DTSTART;TZID=America/Detroit:20260204T160000
DTEND;TZID=America/Detroit:20260204T172000
SUMMARY:Workshop / Seminar:RTG SEMINAR GEOMETRY TOPOLOGY DYNAMICS:  Arithmeticity\, superrigidity\, and totally geodesic submanifolds
DESCRIPTION:In 2018\, Bader and Furman extended Margulis' higher-rank superrigidity theorem using the notion of algebraic representations of ergodic actions\, abbreviated AREA. The idea now is to apply the AREA machinery in the rank-1 setting\, where superrigidity remains a mysterious phenomenon. This talk will serve as a preview for my talk in the Geometry seminar\, where I will discuss recent progress in this direction. In particular\, I will review important elements of Margulis' original proof of superrigidity and provide some context for the recent work of Bader-Fisher-Miller-Stover on the arithmeticity of finite-volume hyperbolic manifolds with infinitely many maximal totally geodesic submanifolds.
UID:144732-21895781@events.umich.edu
URL:https://events.umich.edu/event/144732
CLASS:PUBLIC
STATUS:CONFIRMED
CATEGORIES:Mathematics
LOCATION:East Hall - 3866
CONTACT:
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