报告题目:Stochastic Stability of Invariant Measures for Quasipotential Systems
报告时间:2023-11-06 16:00-17:00
报 告 人 :蒋继发 教授 上海师范大学
报告地点:理学院东北楼四楼学术报告厅(404)
Abstract: A smooth vector field, called quasipotential,
can be generically decomposed into the sum of a gradient vector field and a
divergence-free vector field. This talk first gives the sufficient and
necessary condition for a system to be quasipotentialand then presents the criteria for invariant measures to be stochastically
stable under additive noise perturbation by the Laplace method. It is proved
that limiting measures of stationary measures concentrate on the global minima
set of the potential function. The Laplace method will determine the weights on
components of the global minima set, which gives the stochastically stable
invariant measures. The supports of stochastically stable invariant measures
contain either Lyapunov stable equilibria, or saddles, or periodic orbits, or
quasiperiodic orbits or heteroclinic orbits, or even chaotic motions, while the
most existing results are on gradient systems, supports of their stochastically
stable invariant measures only contain Lyapunov stable equilibria. We also
provide the method how to explicitly compute the transition difficulty matrix
between limit sets by uniform large deviation principles, which again
determines the stochastically stable invariant measures.