Log-Sobolev Inequalities and Markov Semigroups Spring 2025

Lecturer
Yuansi Chen
Lecture Time and Location
Mon 12:15-14:00 (from 17.02.2025 to 26.05.2025), HG E 33.5
Course Number
401-3382-25L
Office Hours
Mon 14:00-15:00 or by email appointment, HG G 15.1

Content

Markov semigroups provide very general models and tools in the analysis of time evolution phenomena and dynamical systems. This course is a modern overview on probabilistic and geometric aspects of Markov semigroups and associated functional inequalities such as log-Sobolev inequalities.

This course focuses on understanding a few topics centered around Markov semigroups and associated functional inequalities. The important topics to master include Markov semigroups, examples of Markov semigroups coming from stochastic differential equations, Poincare inequality, log-Sobolev inequality and isoperimetric inequality.

The main content follows the book "Analysis and Geometry of Markov Diffusion Operators", Bakry, Gentil and Ledoux, 2013.

The official course catalogue page can be found here.

Prerequisites

This course is designed to be accessible for first-year master student in mathematics. A solid background on undergraduate probability and analysis is required. Background on stochastic processes and stochastic differential equations is highly recommended.

Lecture notes

(tentative, please refresh page)
Date Content Notes
Mon 17.02. Introduction to Markov semigroups
Mon 24.02. Model Examples: Euclidean heat semigroup, Ornstein-Uhlenbeck semigroup Week 01-02
Mon 03.03. from OU semigroup to Gaussian Poincaré inequality, log-Sobolev inequality
Mon 10.03. Implications of PI and LSI, alternative proofs Week 03-04
Mon 17.03. Hypercontractivity and spectral gap as reformulation Week 5
Mon 24.03. Transport inequalities Week 6
Mon 31.03. Isoperimetric inequalities Week 7
Mon 07.04. Bakry-Émery criterion and Gamma-calculus Week 8
Mon 14.04. (continued) Week 9
Mon 21.04. No Lecture
Mon 28.04. No Lecture
Mon 05.05. Kannan - Lovász - Simonovits conjecture Week 10
Mon 12.05. Optimal transport viewpoint Week 11
Mon 19.05. (continued) Week 12
Mon 26.05. Discrete space and open problems Week 13
Link to Overleaf exercises

Suggested readings

Week 01-02: Week 03-04: Week 05: Week 06:

Literature