Misc. seminar - math

Date:
Dec
07
2021

Special Seminar

Stable Vortex Sheets and Irreversibility of Turbulence
Alexander Migdal
4:00pm|Simonyi Hall 101 and Remote Access

New kinds of vortex sheets with vorticity confined to the boundary layer are proposed and investigated in detail. Exact solutions of the steady Navier-Stokes equations for a planar vortex sheet in arbitrary background strain are found in terms of...

Dec
08
2021

Character Varieties, Dynamics and Arithmetic

Effective mapping class group dynamics
10:00am|Simonyi Hall 101 and Remote Access
Motivated by counting problems for closed geodesics on hyperbolic surfaces, I will present a family of new results describing the dynamics of mapping class groups on Teichmüller spaces and spaces of closed curves of closed surfaces.
Dec
08
2021

Arithmetic Groups

Commutators in SL_2 and Markoff Surfaces
11:00am|Simonyi 101 and Remote Access

We discuss a local to global profinite principle for being a commutator in some arithmetic groups. Specifically we show that $SL_2(Z)$ satisfies such a principle, while it can fail with infinitely many exceptions for $SL_2(Z[1/p])$. The source of...

Dec
15
2021

Character Varieties, Dynamics and Arithmetic

The dynamics of Aut(Fn) actions on group presentations and representations
10:00am|Simonyi Hall 101 and Remote Access

Several different areas of group theory, topology, and geometry have led to the study of the action of $Aut(Fn)$—the automorphism group of the free group on $n$ generators—on $Hom(Fn, G)$ when $G$ is either finite, compact or a simple Lie group. We...

Dec
15
2021

Arithmetic Groups

Commutators in SL_2 and Markoff Surfaces
11:00am|Simonyi 101 and Remote Access

We discuss a local to global profinite principle for being a commutator in some arithmetic groups. Specifically we show that $SL_2(Z)$ satisfies such a principle, while it can fail with infinitely many exceptions for $SL_2(Z[1/p])$. The source of...