C O L L O Q U I U M


 

New Function Spaces for the Boltzmann Equation

 

Professor Tong YANG

Department of Mathematics

City University of Hong Kong

 

Abstract

We present some well-posedness theories for the Cauchy problem of the Boltzmann equation in some new function spaces. For the case without external force, a new well-posedness theory is obtained for solutions near an absolute Maxwellian in a mild sense without any regularity assumptions. The optimal convergence rates to the equilibrium in various spaces are also given together with the spatial derivatives where no smallness assumptions are imposed on the derivatives of the initial data. For the case with external force, the solution operator is no longer a semi-group so that the analysis becomes complicated. The well-posedness is shown in some Sobolev spaces and the optimal convergence rates are also derived. This kind of research is closely related to the hypercoercivity theory of the Boltzmann equation and has application in the study of other physical problems, such as the time-periodic solutions in the generation and propagation of sound waves.

 

Date:

December 1, 2006 (Friday)

Time:

4:00 – 5:00pm

Place:

Room 517, Meng Wah Complex, HKU

 

 

All are welcome