2023-2024 Seminars

Oct
30
2023

Computer Science/Discrete Mathematics Seminar I

A High Dimensional Goldreich-Levin Theorem
Silas Richelson
11:15am|Simonyi 101 and Remote Access

In this work we prove a high dimensional analogue of the beloved Goldreich-Levin  theorem (STOC 1989), which is the first local list-decoding algorithm.  We consider the following algorithmic problem: given oracle access to a function $f: Z_q^m...

Oct
24
2023

Computer Science/Discrete Mathematics Seminar II

An Optimization Perspective on Log-Concave Sampling
10:30am|Simonyi Hall 101 and Remote Access

I will give an introduction to the problem of sampling from a strongly log-concave density on Euclidean space through the lens of convex optimization.  In particular, I will focus on the interpretation, due to Jordan, Kinderlehrer, and Otto, of the...

Oct
23
2023

Computer Science/Discrete Mathematics Seminar I

A Proof of the RM Code Capacity Conjecture
Emmanuel Abbé
11:15am|Simonyi 101 and Remote Access

In 1948, Shannon used a probabilistic argument to show the existence of codes achieving channel capacity. In 1954, Muller and Reed introduced a simple deterministic code construction, conjectured shortly after to achieve channel capacity. Major...

Oct
17
2023

Computer Science/Discrete Mathematics Seminar II

Extending Generalization Theory to Address Phenomena in Contemporary Machine Learning
Shay Moran
10:30am|Simonyi Hall 101 and Remote Access

Recent years have seen remarkable progress in the field of Machine Learning (ML). 

However recent breakthroughs exhibit phenomena that remain unexplained and at times contradict conventional wisdom.  A primary reason for this discrepancy is that...

Oct
16
2023

Computer Science/Discrete Mathematics Seminar I

A Combinatorial Characterization of Minimax in 0/1 Games
Shay Moran
11:15am|Simonyi 101 and Remote Access

We will discuss a generalization of the celebrated Minimax Theorem (von Neumann, 1928) for binary zero-sum games. A simple game which fails to satisfy Minimax is Ephraim Kishon's “Jewish Poker” (see [1,2] below). In this game, each player picks a...

Oct
10
2023

Computer Science/Discrete Mathematics Seminar II

Shrinkage Under Random Restrictions
10:30am|Simonyi Hall 101 and Remote Access

Random restrictions are a powerful tool used to study the complexity of boolean functions. Various classes of boolean circuits are known to simplify under random restrictions. A prime example of this, discovered by Subbotovskaya more than 60 years...

Oct
09
2023

Computer Science/Discrete Mathematics Seminar I

Private Optimization and Statistical Physics: Low-Rank Matrix Approximation
Nisheeth Vishnoi
11:15am|Simonyi 101 and Remote Access

In this talk, I will present the following two connections between private optimization and statistical physics, both via the problem of approximating a given covariance matrix with a low-rank matrix:

  1. An efficient algorithm to privately compute a...
Oct
03
2023

Computer Science/Discrete Mathematics Seminar II

Learning from Dynamics
Ankur Moitra
10:30am|Simonyi Hall 101 and Remote Access

Linear dynamical systems are the canonical model for time series data. They have wide-ranging applications and there is a vast literature on learning their parameters from input-output sequences. Moreover they have received renewed interest because...

Oct
02
2023

Computer Science/Discrete Mathematics Seminar I

The Diffraction Limit and Extremal Functions
Ankur Moitra
11:15am|Simonyi 101 and Remote Access

It is widely believed that the physics of diffraction imposes certain fundamental limits on the resolution of an optical system. In this work we study the diffraction limit as a statistical inverse problem in increasingly more realistic mathematical...

Sep
19
2023

Computer Science/Discrete Mathematics Seminar II

Optimization, Complexity and Math (or, Can We Prove P!=NP by Gradient Descent?).
10:30am|Simonyi Hall 101 and Remote Access

This talk will summarize a project I was involved in during the past 8 years. It started with attempts to understand the PIT (Polynomial Identity Testing) problem - a central problem involving randomness and hardness. It has led us to pursue many...