Scientific Lectures

  • 26-Apr-07
  • 25-Apr-07

Prandtl Conjecture and von Neumann Paradox for Shock Reflections

We plan to discuss the two fundamental problems, the Prandtl Conjecture and von Neumann Paradox, in the theory of supersonic flows with shock waves. These problems were raised in the first half of the 20th century and clearly formulated in the cla   more››

University of British Columbia

  • 24-Apr-07

The sharp isoperimetric inequality on minimal submanifolds

We will describe the history of the conjecture that the isoperimetric inequality with the Rn constant should hold for a domain on a minimal submanifold of dimension n in Euclidean space. We will then describe a new method which pr   more››

University of Washington

  • 24-Apr-07

Probability and Recursion

Mihalis Yannakakis is the Percy K. and Vida L. W. Hudson Professor of Computer Science at Columbia University. Prior to joining Columbia, he was Director of the Computing Principles Research Department at Bell Labs (1991-2001) and at Avaya Labs (2   more››

Simon Fraser University

  • 19-Apr-07

Scheduling, Percolation, and the Worm Order

When can you schedule a multi-step process without having to take backward steps? Critical are an old concept called "submodularity", a new structure called the "worm order", and a variation of what physicists call "percol   more››

University of Washington

  • 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
  • 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

Homogenization results for dislocation dynamics

TBA   more››

University of British Columbia

  • 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

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