Previous Conferences & Workshops

Oct
13
2011

Workshop on Symplectic Dynamics

Higher pentagram maps and cluster algebras
Serge Tabachnikov
9:00am|Wolfensohn Hall
Introduced by R. Schwartz about 20 years ago, the pentagram map acts on plane n-gons, considered up to projective equivalence, by drawing the diagonals that connect second-nearest vertices and taking the new n-gon formed by their intersections. The...
Oct
12
2011

Workshop on Symplectic Dynamics

Some intersection and rigidity properties in symplectic dynamics
Jeff Xia
4:30pm|Wolfensohn Hall
We will explore some connections between Hamiltonian dynamics and the geometry of symplectic manifolds. We show some intersection properties between isotropic and coisotropic submanifolds, with applications to hoteroclinic connections in Hamiltonian...
Oct
12
2011

Workshop on Symplectic Dynamics

KAM-Tori accumulating a Diophantine elliptic equilibrium point
Hakan Eliasson
2:30pm|Wolfensohn Hall
We prove that an elliptic equilibrium point with Diophantine frequencies for an analytic Hamiltonian system is always accumulated by invariant Lagnrangian tori. Generically the set of such tori has positive measure, but if this is always the case is...
Oct
12
2011

Workshop on Symplectic Dynamics

Regularity of weak KAM
Chong-Qing Cheng
11:30am|Wolfensohn Hall
In this talk, I will show some modulus of continuity of weak KAM solutions exhibited by Hamiltonian with multi-degrees of freedom.
Oct
12
2011

Workshop on Symplectic Dynamics

Using pseudo-holomorphic curves to approximate zero entropy Hamiltonian systems by integrable ones
Barney Bramham
10:15am|Wolfensohn Hall
Katok has asked the following informal question: In low dimensions are all conservative dynamical systems with zero topological entropy a limit of integrable systems? In this talk I will discuss an approach to this question that uses pseudo...
Oct
11
2011

Joint IAS/Princeton University Mathematical Physics Seminar

Absence of Mobility Edge for the Anderson Random Potential on Tree Graphs at Weak Disorder
Simone Warzel
4:30pm|Princeton University, A06 Jadwin Hall

We discuss recently established criteria for the formation of extended states on tree graphs in the presence of disorder. These criteria have the surprising implication that for bounded random potentials, as in the Anderson model, in the weak...

Oct
11
2011

Workshop on Symplectic Dynamics

Generic symplectic diffeomorphisms and partial hyperbolicity
Jairo Bochi
4:30pm|Wolfensohn Hall
I will talk about the following theorem: If $f$ is a $C^1$ generic symplectic diffeomorphism of a compact manifold then the Oseledets splitting along almost every orbit is partially hyperbolic or trivial; in addition, if $f$ is not Anosov then all...
Oct
11
2011

Workshop on Symplectic Dynamics

Resonance identities and closed characteristics on compact star-shaped hypersurfaces in R2n
Yiming Long
2:30pm|Wolfensohn Hall
Recently two new resonance identities on closed characteristics on every compact star-shaped hypersurface $\Sigma$ in $R^{2n}$ are proved, when the number of geometrically distinct closed characteristics on $\Sigma$ is finite. These identities...
Oct
11
2011

Workshop on Symplectic Dynamics

Action-index relations for Hamiltonian dynamical systems
Victor Ginzburg
11:30am|Wolfensohn Hall
In this talk we discuss Hamiltonian diffeomorphisms with finitely many periodic orbits. We show that, under suitable additional hypotheses on the ambient manifold, the actions and mean indexes of periodic orbits of such a diffeomorphism must satisfy...
Oct
11
2011

Computer Science/Discrete Mathematics Seminar II

Limit Theories and Higher Order Fourier Analysis
Balazs Szegedy
10:30am|S-101

We present a unified approach to various topics in mathematics including: Ergodic theory, graph limit theory, hypergraph regularity, and Higher order Fourier analysis. The main theme is that very large complicated structures can be treated as...