Kathryn Mann- Groups Acting at Infinity

Explore the fascinating world of group actions and rigidity in mathematics through this 43-minute lecture by Kathryn Mann. Delve into the concepts of rigidity in group actions and lattices before venturing into the realm of infinity. Discover new forms of rigidity emerging from infinite perspectives, with a focus on dimension 1 and C-stability for surface groups. Examine the proof idea through a simplified illustration and explore various applications of this philosophical approach. Investigate boundaries and coarse hyperbolicity, leading to boundary rigidity. Conclude by classifying Anosov flows on manifolds and flows up to orbit equivalence, utilizing rigidity at infinity as a powerful tool in the proof process.

Intro
Rigidity of group actions
Rigidity of lattices
Looking to infinity
New rigidity from infinity
I. Dimension 1
C-stability for surface groups at infinity
Proof idea (cartoon)
Applications of same philosophy
II. Boundaries - coarse hyperbolicity
Boundary rigidity
III. Classifying Anosov flows on M
Classifying flows up to orbit equivalence
Proof via rigidity at infinity