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DTSTART;TZID=America/Chicago:20260417T140000
DTEND;TZID=America/Chicago:20260417T150000
DTSTAMP:20260425T034604Z
SUMMARY:Arithmetic Groups Seminar | Stepan Alexandrov (Bonn/MPIM)
UID:641659@northwestern.edu
TZID:America/Chicago
DESCRIPTION:Title: Family of hyperbolic manifolds with exponential homology torsion growth  Abstract: We discuss a recent construction of a family of compact hyperbolic manifolds whose homology torsion grows exponentially with respect to volume. This shows that the upper bounds on torsion growth obtained by Bader\, Gelander\, and Sauer are asymptotically sharp.  The construction is based on arithmetic hyperbolic manifolds of simplest type and uses right-angled Coxeter groups together with retraction techniques inspired by Bergeron–Haglund–Wise. A key ingredient is the existence of sufficiently many “independent” totally geodesic submanifolds\, which produce large torsion in homology.  We outline the main ideas of the construction and discuss the geometric mechanisms behind exponential torsion growth.
LOCATION:Lunt Hall\, 103\, 2033 Sheridan Road\, Evanston\, IL 60208
TRANSP:OPAQUE
URL:https://planitpurple.northwestern.edu/event/641659
CREATED:20260413T050000Z
STATUS:CONFIRMED
LAST-MODIFIED:20260414T161255Z
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