Previous Conferences & Workshops

Apr
07
2016

Joint IAS/Princeton University Symplectic Geometry Seminar

Classification results for two-dimensional Lagrangian tori
Georgios Dimitroglou-Rizell
11:00am|S-101

We present several classification results for Lagrangian tori, all proven using the splitting construction from symplectic field theory. Notably, we classify Lagrangian tori in the symplectic vector space up to Hamiltonian isotopy; they are either...

Apr
07
2016

Joint IAS/Princeton University Symplectic Geometry Seminar

Stein fillings of cotangent bundles of surfaces
Jeremy van Horn Morris
9:45am|S-101

I'll outline recent results with Steven Sivek classifying the Stein fillings, up to topological homotopy equivalence, of the canonical contact structure on the unit cotangent bundle of a surface. The proof begins with Li, Mak and Yasui's technology...

Apr
06
2016

Mathematical Conversations

Entrance path category of a stratified space
6:00pm|Dilworth Room

A covering space $C \\to M$ is classified by a subgroup of the fundamental group of $M$. If we refuse to choose a basepoint, then $C \\to M$ is equivalent to a functor from the fundamental groupoid of $M$ to $\\mathsf{Set}$. Suppose $(M,S)$ is a...

Apr
06
2016

Analysis Seminar

Quantum Yang-Mills theory in two dimensions: exact versus perturbative
Timothy Nguyen
11:00am|S-101

The conventional perturbative approach and the nonperturbative lattice approach are the two standard yet very distinct formulations of quantum gauge theories. Since in dimension two Yang-Mills theory has a rigorous continuum limit of the lattice...

Apr
05
2016

Geometric Structures on 3-manifolds

Collapsing hyperbolic structures: from rigidity to flexibility and back
Steve Kerckhoff
2:00pm|S-101

This talk will be about some phenomena that occur as (singular) hyperbolic structures on 3-manifolds collapse to and transition through other geometric structures. Typically, the collapsed structures are much more flexible than the hyperbolic...

Apr
05
2016

Computer Science/Discrete Mathematics Seminar II

An average-case depth hierarchy theorem for Boolean circuits II
Li-Yang Tan
10:30am|S-101

We prove an average-case depth hierarchy theorem for Boolean circuits over the standard basis of AND, OR, and NOT gates. Our hierarchy theorem says that for every $d \geq 2$, there is an explicit $n$-variable Boolean function $f$, computed by a...

Apr
04
2016

Members’ Seminar

Knot surgery and Heegaard Floer homology
2:00pm|S-101

One way to construct new 3-manifolds is by surgery on a knot in the 3-sphere; that is, we remove a neighborhood of a knot, and reglue it in a different way. What 3-manifolds can be obtained in this manner? We provide obstructions using the Heegaard...

Apr
04
2016

Computer Science/Discrete Mathematics Seminar I

An average-case depth hierarchy theorem for Boolean circuits I
Li-Yang Tan
11:15am|S-101

We prove an average-case depth hierarchy theorem for Boolean circuits over the standard basis of AND, OR, and NOT gates. Our hierarchy theorem says that for every $d \\geq 2$, there is an explicit $n$-variable Boolean function $f$, computed by a...

Apr
01
2016

Joint IAS/Princeton/Columbia Symplectic Geometry Seminar

Infinitely many monotone Lagrangian tori in Del Pezzo surfaces
Renato Vianna
1:00pm|Math 407, Columbia University

We will describe how to get almost toric fibrations for all del Pezzo surfaces (endowed with monotone symplectic form), in particular for $\\mathbb{CP}^2\\#k\\overline{\\mathbb{CP}}^2$ for $4\\le k \\le 8$, where there is no toric fibrations. From...