Previous Conferences & Workshops

Oct
19
2022

Special Year Learning Seminar

Fraisse Limits and Tensor Spaces
10:30am|Simonyi 101 and Remote Access

In model theory Fraisse limits are certain highly homogeneous countable structures -- examples include the rational numbers as the unique dense linear order without endpoints, and the Rado graph as the "unique infinite random graph".  I will discuss...

Oct
18
2022

Special Year Research Seminar

Word Width in Higher Rank Arithmetic Groups
4:00pm|Simonyi 101 and Remote Access

A word on d letters is an element of the free group of rank d, say, with basis x_1,…,x_d. Given a word w=w(x_1,…,x_d) on d letters, for every group G, there is a word map w:G^d—> G given by substituting the x_i’s with elements of G. We say that a...

Oct
18
2022

Special Year Research Seminar

Linear Equations in Smooth Numbers
Lilian Matthiesen
2:00pm|Simonyi 101 and Remote Access

A number is called y-smooth if all of its prime factors are bounded above by y. The set of y-smooth numbers below x forms a sparse subset of the integers below x as soon as x is sufficiently large in terms of y. If f_1, …, f_r \in Z[x_1,…,x_s] is a...

Oct
18
2022

Guangbo Xu's Seminar

AMS construction for Floer moduli spaces
1:00pm|West Lecture Hall and Remote Access

I will explain how to generalize Abouzaid-McLean-Smith's construction to Floer moduli spaces. As we need to regularize infinitely many moduli spaces, we need to make choices consistently. We also need to generalize the smoothing theory to the...

Oct
18
2022

Computer Science/Discrete Mathematics Seminar II

Almost Linear Time Algorithms for Max-flow and More
10:30am|Simonyi Hall 101 and Remote Access

We give the first almost-linear time algorithm for computing exact maximum flows and minimum-cost flows on directed graphs. By well known reductions, this implies almost-linear time algorithms for several problems including bipartite matching...

Oct
17
2022

Joint IAS/Princeton University Symplectic Geometry Seminar

Three-dimensional Anosov flows and non-Weinstein Liouville domains.
Thomas Massoni
4:00pm|Simonyi 101 and Remote Access

An Anosov flow $\Phi$ on a closed $3$-manifold $M$ gives rise to a non-Weinstein Liouville structure on $V:=[-1,1] \times M$. Building upon the work of Hozoori, we establish a homotopy correspondence between Anosov flows and certain pairs of contact...

Oct
17
2022

Members' Colloquium

Noetherianity up to Symmetry
2:00pm|Simonyi Hall 101 and Remote Access - see Zoom link below

Noetherianity is a fundamental property of modules, rings, and topological spaces that underlies much of commutative algebra and algebraic geometry. This talk concerns algebraic structures such as the infinite-dimensional polynomial ring K[x_1,x_2...

Oct
17
2022

Computer Science/Discrete Mathematics Seminar I

The Optimal Error Resilience of Interactive Communication over the Binary Alphabet
Rachel Zhang
11:15am|Simonyi 101 and Remote Access

In interactive coding, Alice and Bob wish to compute some function f of their private inputs x and y. They do this by engaging in a non-adaptive (fixed speaking order, fixed length) protocol to jointly compute f(x,y). The goal is to do this in an...

Oct
14
2022

Guangbo Xu's Seminar

Derived orbifold chart lifts of flow categories and bimodules
1:00pm|Simonyi 101 and Remote Access

In Hamiltonian Floer theory one needs to regularize infinitely many moduli spaces. It is convenient to formalize the discussion using the language of flow categories and bimodules. In this lecture I will explain how to use the notion of "derived...

Oct
14
2022

Probability Seminar

Massless Phases for the Villain Model in $d>=3$
Wei Wu
11:15am|Simonyi 101 and Remote Access

The XY and the Villain models are models which exhibit the celebrated Kosterlitz-Thouless phase transitions in two dimensions. The spin wave conjecture, originally proposed by Dyson and by Mermin and Wagner, predicts that at low temperature, spin...