Abstract: I will survey (in)coherence of lattices in semisimple
Lie groups, with a view toward open problems and connections with
the geometry of locally symmetric spaces. Particular focus will be
placed on rank one lattices, where I will discuss...
Abstract: There seems to be an analogy between the classes of
fundamental groups of compact 3-manifolds and of one-relator
groups. (Indeed, many 3-manifold groups are also one-relator
groups.) For instance, Dehn’s Lemma for 3-manifolds (proved
Abstract: This will be a broad talk about coherence of groups,
and how it relates to conjectures about hyperbolic groups with
planar boundaries. A group is coherent if every finitely generated
subgroup is finitely presented. This is a property...
Abstract: Consider the defocusing cubic Schrödinger
equation defined in the 2 dimensional torus. It has as a subsystem
the one dimension cubic NLS (just considering solutions depending
on one variable). The 1D equation is integrable and admits...
Abstract: Arnold diffusion studies the problem of topological
instability in nearly integrable Hamiltonian systems. An important
contribution was made my John Mather, who announced a result in two
and a half degrees of freedom and developed deep...
Abstract: We consider a geometric framework that can be applied to
prove the existence of drifting orbits in the Arnold diffusion
problem. The main geometric objects that we consider are
3-dimensional normally hyperbolic invariant cylinders with...