## Scientific Lectures

- 19-Apr-07

Gauss Sums: Finding the Root of Unity

A Gauss sum over a finite field GF(q) is a sum of q algebraic numbers. It is often useful to evaluate Gauss sums explicitly, for instance, in coding theoretic or cryptographic applications. For small q, the evaluation of Gauss sums can be done nai more››

University of Calgary

- 19-Apr-07

A unified approach to modelling trajectories

The talk will concern the employment of stochastic gradient systems in the modeling and statistical analysis of biological and ecological processes of moving particles. The work is stimulated by scientific questions and data sets of the movements more››

Simon Fraser University

- 18-Apr-07

Braid groups of the projective plane and the splitting problem

TBA more››

University of British Columbia

- 18-Apr-07

Random walk on the incipient infinite cluster for oriented percolation

We consider simple random walk on the incipient infinite cluster for the spread-out model of oriented percolation in d spatial dimensions and one time dimension. For d>6, we obtain bounds on exit times, transition probabilities, and the range o more››

University of British Columbia

- 18-Apr-07

Values and Ideals in Combinatorial Problems

The absolute value of complex numbers is surprisingly useful in the investigation of certain combinatorial problems. The connection often arises from imbedding finite cyclic groups into the complex numbers by sending the group elements to roots of more››

University of Calgary

- 17-Apr-07

- 17-Apr-07

Recent developments on the well-posedness of dispersive equations

We will review the progress in the last 20 years on the well-posedness theory of dispersive equations, concentrating in the case of the Korteweg- de Vries equation to illustrate it. We will then describe some of the current challenges in the area, more››

University of Washington

- 16-Apr-07

Algebraic Topology and Geometric Pattern Recognition

With the "blizzard" of data being generated by scientists in all disciplines, the development of tools for analyzing it has become a very high priority task. In particular, methods for quick qualitative analysis are of particular value. more››

University of British Columbia

- 12-Apr-07

Gerbes in orbifold cohomology and mirror symmetry

I will explain why twisting by a gerbe is a natural operation in both orbifold cohomology and mirror symmetry, and show how many examples of Calabi-Yau orbifolds whose twisted orbifold Hodge numbers are mirror to each other may be easily constructed. more››

University of British Columbia

- 10-Apr-07

Quantum Mechanics, the Stability of Matter, and Quantum

Ordinary matter is held together with electromagnetic forces, and the dynamical laws governing the constituents (electrons and nuclei) are those of quantum mechanics. These laws, found in the beginning of last century, were able to account for the more››

University of Washington

- 9-Apr-07

10th Anniversary Speaker Series 2007

The peculiar quantum-mechanical properties of the ground states of Bose gases that were predicted in the early days of quantum-mechanics have been verified experimentally relatively recently. The mathematical derivation of these properties from Sc more››

University of Washington

- 5-Apr-07

Evolutionary branching is sympatric speciation driven by competition between dominant species and their mutants. The traditional approach to study evolutionary branching is to use pairwise-invasibility plot (PIP). However, PIP is only suitable for more››

University of British Columbia

- 4-Apr-07

Two Dimensional Lotka-Volterra Models and Superprocesses

Neuhauser and Pacala (99) introduced a particle system to model the dynamics of two competing types on an integer lattice. We study the model near the parameter values for which there is a cross-over from preference of one's own type to preference more››

University of British Columbia

- 3-Apr-07

Conservation of the combinatorial structure in genome

We investigate the problem of computing an evolution scenario based on genome rearrangements between two genomes modelized by synteny blocks, or in mathematical terms, sorting signed permutations by reversals. We consider the case of scenarios tha more››

University of British Columbia

- 3-Apr-07

The oldest competition for an optimal shape (area-maximizing) was won by the circle. We want to give the thousandth proof ! Then we measure the perimeter in different ways, which changes the problem (and has applications in medical i more››

Simon Fraser University

- 2-Apr-07

Asymptotic behavior at infinity of solutions of elliptic equations

The prototype problem is the behavior at infinity of all solutions of a linear elliptic equation that have finite L1 norm in a half cylinder 0<y, x in D,D a smoothly bounded domain. We assume that the coefficients of the elliptic operator,as we more››

University of British Columbia

- 2-Apr-07

Statistical Models for Global Processes

This talk explores some of the issues that arise in statistical modeling of atmospheric phenomena on a global scale, using total column ozone as measured by the satellite-based Total Ozone Mapping Spectrometer (TOMS) as a case study. A basic issue more››

University of British Columbia

- 30-Mar-07

A Phragmen-Lindelof and Saint Venant principle in harmonic analysis

Let S be a linear space of vector valued functions u(y) on the half-line whose values belong to some Banach space. We suppose that S is translation invariant; that is, if u(y) belongs to S, so does u(y+t) for all t>0. S is called 'interior comp more››

University of Washington

- 29-Mar-07

Fake 2-descent on the Jacobian of a genus-3 curve

For many questions in explicit arithmetic geometry of curves, one needs detailed information on the rational points of the Jacobian of the curve. A first step is to bound the free rank of the finitely generated group that they form. For hyperellip more››

University of British Columbia

- 29-Mar-07

Data Stream Processing with Resource Adaptive Computation

The problem of streaming data has gained importance in recent years because of advances in hardware technology. The ubiquitous presence of data streams in a number of practical domains has generated a lot of research in this area. Example applicat more››

Simon Fraser University