2006-2007 seminars

Nov
13
2006

Computer Science/Discrete Mathematics Seminar I

Coupon Go
Elwyn Berlekamp
11:15am|S-101

Decomposition and modularity are fundamental issues in many fields, including mathematics, biology, engineering, and management. How can large systems be broken into subsystems which interact enough to meet the overall system goals, but not so much...

Nov
07
2006

Computer Science/Discrete Mathematics Seminar II

Solvability of Polynomial Equations over Finite Fields
10:30am|S-101

We investigate the complexity of the following polynomial solvability problem---given a finite field $\mathbb F_q$ and a set of polynomials $f_1, f_2, \dotsc, f_m \in \mathbb F_q[x_1, x_2, \dotsc, x_n]$ of total degree at most $d$, determine the...

Nov
06
2006

Computer Science/Discrete Mathematics Seminar I

Towards Harmful Low-Rate Noise Models for Quantum Computers
11:15am|S-101

We propose and discuss two conjectures on the nature of errors in highly correlated noisy physical stochastic systems. The first asserts that errors for a pair of substantially correlated elements are themselves substantially correlated. The second...

Oct
31
2006

Computer Science/Discrete Mathematics Seminar II

2-Source Dispersers for Sub-Polynomial Min-Entropy and Ramsey Graphs Beating the Frankl Wilson Construction
10:30am|S-101

The main result of this work is an explicit disperser for two independent sources on $n$ bits, each of entropy $k=n^{o(1)}$. Put differently, setting $N=2^n$ and $K=2^k$, we construct explicit $N \times N$ Boolean matrices for which no $K \times K$...

Oct
30
2006

Computer Science/Discrete Mathematics Seminar I

2-Source Dispersers for n^{o(1)} Entropy, and Ramsey Graphs Beating theFrankl-Wilson Construction
11:15am|S-101

The main result of this work is an explicit disperser for two independent sources on n bits, each of entropy k=n^{o(1)}. Put differently, setting N=2^n and K=2^k, we construct explicit N by N Boolean matrices for which no K by K submatrix is...

Oct
17
2006

Computer Science/Discrete Mathematics Seminar II

An Invitation to Combinatorial Games
10:30am|S-101

Combinatorial game theory is the study of combinations of two-player games with no hidden information and no chance elements. The subject has its roots in recreational mathematics, but in its modern form involves a rich interplay of ideas borrowed...

Oct
16
2006

Computer Science/Discrete Mathematics Seminar I

Randomness-Efficient Sampling Within NC^1
Alex Healy
11:15am|S-101

It is now well-known that a random walk on an expander graph is a very good "sampler", and this has been used to prove a variety of important results in complexity theory, cryptography and algorithms. On the surface, however, taking a walk on an...

Oct
10
2006

Computer Science/Discrete Mathematics Seminar II

An Invitation to Combinatorial Games
10:30am|West Building Lecture Theatre

Combinatorial game theory is the study of combinations of two-player games with no hidden information and no chance elements. The subject has its roots in recreational mathematics, but in its modern form involves a rich interplay of ideas borrowed...