Past Events

A set is Kakeya if it contains a line in every direction. We prove that every Kakeya set in the n-space over F_q has at least 2^{-n+1}*q^n elements. This is

This talk will discuss a (relatively) new method for integration. It was developed by Ivan Gonzalez as part of his PhD thesis in the analysis of Feynman diagram. A large

In this talk, we discuss the max-weight stochastic matchings on online bipartite graphs under both vertex and edge arrivals. We will present polynomial-time approximation algorithms with respect to the online

There's a function not unlike the ordinary chromatic function which is defined via colorings of a graph. But this function, defined as a polynomial in countably many variables, has other

A central open problem in Ramsey theory is to determine the behavior of r_3(t), the minimum n such that any 2-coloring of the complete 3-uniform hypergraph on n vertices contains

Consider the complete graph whose vertices are the n-th roots of unity in the complex plane. To every edge between a pair of vertices, associate a weight that is a

We study a simple model of epidemics where an infected node transmits the infection to its neighbors independently with probability p. The size of an outbreak in this model is

A family of subsets is cancellative if A U B = A U C implies B = C for any A,B,C in the family. Frankl and Furedi proved an upper

We extend the classical definition of patterns in permutations to parking functions. In particular we study parking functions that avoid permutations of length 3. A number of well-known combinatorial sequences

Multidimensional packing problems generalize the standard packing problems such as Bin Packing, Multiprocessor Scheduling by allowing the jobs to be d-dimensional vectors. While the approximability of the scalar problems is

Graph coloring is a central topic in combinatorics with many applications, from maps to chemistry refrigerators. An instance of a list coloring problem inputs a graph G=(V,E) together with sets

James Joseph Sylvester was the first one to find a determinant solution of a system of nonlinear differential equations which is now known as Toda system. I will talk about

Over the past several years, enormous progress has been made in our understanding of communication complexity, including solving several long-standing open problems. One area where many open problems remain is

If we let v(G) be the maximal cardinality of a set of pairwise disjoint triangles in G, and t(G) be the minimal cardinality of an edge cover with an edge

Mancala games have fascinated people worldwide for centuries, and Tchoukaillon is a particularly nice specimen of such a game. I will indicate how it might help to answer the following

Error-correcting codes protect data from noise. Deletion errors are pervasive, yet codes correcting deletions are poorly understood. I will discuss recent work that answers an extremely basic deletion codes question:

In recent years quantum computers moved much closer to reality. There are a number of companies that are making rapid progress toward building a large-scale quantum computer. In particular, IBM

Complexity theory is generally a two-handed piece between the upper bound O(f(n)) algorithm designers and the lower bound Ω(f(n)) example builders. If they agree, we're in Θ(f(n)) paradise. Implicit in

For an $n$-vertex digraph $G=(V,E)$, a emph{shortcut set} is a (small) subset of edges $H$ taken from the transitive closure of $G$ that, when added to $G$ guarantees that the

A recurring problem in extremal discrete geometry is to ask for an upper or lower bound on the number of instances of a certain configuration in a set of n