Colloquium

The Department of Mathematical Sciences at Lakehead University runs about 5 to 6 colloquiums a year, on an irregular schedule.  

FRIDAY, APRIL 6, 2018

Dr. Wei Sun, Professor, Department of Mathematics & Statistics, Concordia University 

Title:  A System of Nonlinear Equations with Application to Large Deviations

Date: Friday, April 06, 2018

Time: 10:00 - 11:00

Room: RB 1022
 
Please click here to view the abstract 

 

 

TUESDAY, MARCH 13, 2018

Dr. Xiaowen Zhou, Professor,

Department of Mathematics & Statistics

Concordia University 

"Extinction, Explosion and Coming Down from Infinity for Nonlinear

Continuous-State Branching Processes"

Date: Tuesday, March 13, 2018
Time: 3:30 - 4:30
Room: RB 1023

Abstract:  A continuous-state branching process can be  identified as the unique 
nonnegative solution to a SDE driven by a Brownian motion and a compensated Poisson random measure; see Bertoin and Le Gall (2006) and Dawson and Li (2012). By adapting this SDE, we can introduce a continuous-state branching process with nonlinear branching mechanism. Intuitively, the  solution to the modified SDE is a branching process  with branching rates depending on the current population size.
 
Using a martingale approach, we  study its survival/extinction behaviors and find respective sufficient conditions on the branching rate functions under which the process either survives with probability one or dies out with a positive probability, respectively. Similarly, we can also discuss the explosion and the coming down from infinity behaviors of the continuous-state nonlinear branching process. We will show 
that those conditions are quite sharp.
 
This talk is based on joint work with Peisen Li and Xu Yang.

 

 

 

FRIDAY, MARCH 16, 2018

ENERGY DRIVEN SYSTEMS FROM LIQUID CRYSTALS AND EPITAXY

presented by

Dr. Xin Yang Lu, Assistant Professor

Department of Mathematical Sciences

Friday, March 16, 2018

9:30 am

RB 1022

 
Abstract: Epitaxy is a process in which a thin film is grown above a much thicker substrate. Even in the simplest case, with no deposition, and purely elastic interactions, such growth leads to a nonuniform film thickness  since the film and the substrate can have different rigidity constants. The resulting system is thus an energy driven one, but quite irregular.  Similarly, the evolution of nematic liquid crystals, systems is modeled by a highly complex energy driven system. In this talk I will present some recent results about the regularity of solutions to several equations arising from nematic liquid crystals and epitaxy.