2023-2024 Seminars

Apr
08
2024

Computer Science/Discrete Mathematics Seminar I

Polynomial Capacity and its Applications: To TSP and Beyond
Jonathan Leake
11:00am|Simonyi 101 and Remote Access

About 20 years ago, Gurvits developed the notion of polynomial capacity to give a simple proof of the famous van der Waerden lower bound on the permanent of a doubly stochastic matrix. Since then, similar techniques have led to various other...

Apr
02
2024

Computer Science/Discrete Mathematics Seminar II

New Derandomized Agreement Testers
10:30am|Simonyi Hall 101 and Remote Access

Agreement testing (aka direct product testing), checks if consistent local information reveals global structure. Beyond its theoretical connections to probabilistic checkable proofs (PCPs), constructing agreement testers is a fundamental...

Apr
01
2024

Computer Science/Discrete Mathematics Seminar I

Tight Cell-Probe Lower Bounds for Dynamic Succinct Dictionaries
Huacheng Yu
11:00am|Simonyi 101 and Remote Access

A dictionary data structure maintains a set of at most $n$ keys from the universe $[U]$ under key insertions and deletions, such that given a query $x\in[U]$, it returns if $x$ is in the set. Some variants also store values associated to the keys...

Mar
19
2024

Computer Science/Discrete Mathematics Seminar II

Geodesics and Minimal Surfaces in a Random Environment
10:30am|Simonyi Hall 101 and Remote Access

Endow the edges of the $Z^D$ lattice with positive weights, sampled independently from a suitable distribution (e.g., uniformly distributed on [a,b] for some b>a>0). We wish to study the geometric properties of the resulting network, focusing on the...

Mar
18
2024

Computer Science/Discrete Mathematics Seminar I

Computationally Sound Proofs of Network Properties
Rotem Oshman
11:00am|Simonyi 101 and Remote Access

In distributed certification, our goal is to certify that a network has a certain desired property, e.g., the network is connected, or the internal states of its nodes encode a valid spanning tree of the network. To this end, a prover generates...

Mar
12
2024

Computer Science/Discrete Mathematics Seminar II

The Structure of Translational Tilings in Z^d
10:30am|Simonyi Hall 101 and Remote Access

A finite set $F$ in $\mathbb{Z}^d$ is a translational tile of  $\mathbb{Z}^d$ if one can cover  $\mathbb{Z}^d$ by translated copies of $F$ without any overlaps, i.e., there exists a translational tiling of $\mathbb{Z}^d$ by $F$.  Suppose that $F$ is...

Mar
11
2024

Computer Science/Discrete Mathematics Seminar I

Sparsification of Gaussian Processes
Anindya De
11:00am|Simonyi 101 and Remote Access

In this talk, we will show that the supremum of any centered Gaussian process can be approximated to any arbitrary accuracy by a finite dimensional Gaussian process where the dimension of the approximator is just dependent on the target error. As a...

Mar
05
2024

Computer Science/Discrete Mathematics Seminar II

Locally Consistent Decomposition of Strings with Applications to Edit Distance Sketching
Michal Koucký
10:30am|Simonyi Hall 101 and Remote Access

Edit distance is a similarity measure for strings that counts how many characters have to be deleted, inserted or substituted in one string to get another one. It has many applications from comparing DNA sequences to text processing. We are still in...

Mar
04
2024

Computer Science/Discrete Mathematics Seminar I

Explicit SoS Lower Bounds from High Dimensional Expanders
Max Hopkins
11:00am|Simonyi 101 and Remote Access

Where are the hard problems? In the absence of a proof of P ≠ NP, researchers have spent years proving unconditional lower bounds for constrained models of computation. In time, a distinct theme arose: random problems (in particular random...

Feb
27
2024

Computer Science/Discrete Mathematics Seminar II

Computing Greatest Common Divisors of Polynomials in Parallel
10:30am|Simonyi Hall 101 and Remote Access

Given two univariate polynomials, how does one compute their greatest common divisor (GCD)? This problem can be solved in polynomial time using the Euclidean algorithm, and even in quasi-linear time using a fast variant of the Euclidean algorithm...