Measure Theory for Probabilists (WS 2024)

Prof. Dr. Peter Pfaffelhuber

Samuel Adeosun

This is a hybrid course which is given at the University of Freiburg. Lectures will be given with videos (see below). Tutorials take place in person, Wednesdays at 10:15 in Hörsaal II (Albertstr. 23b), starting 16th of October, 2024.

Requirements: If you want to have a Studienleistung, you must get no less than 50% of all points on the exercise sheets, and present a solution of an exercise twice during the tutorials in the semester. If you want to have a Prüfungsleistung, you must pass the exam.

Content: The course covers the material which is usually needed in order to dive into measure theoretic aspects of probability theory. Usually, in basic lectures on probability (e.g. taught in Freiburg as Stochastik 1 in the 3rd semester), no measure theory is needed. Rather, the lecture in Analysis 3 covers measure theory. However, in case you want to specialize in probability theory and did not attend Analysis 3, this course is for you.

Prerequisites: You need to know fundamentals of mathematics, such as sets, functions etc. The course requires some knowledge in topology, but tries to recall all explanations in this field.

Manuscript: The current version is here.

Videos: Below you find links to all Videos, or you look at the playlist. A collection of all slides is here.

Exercise sheets: The homeworks are handed out on Wednesdays, and must be handed in by Tuesday, 10:00. It is allowed to hand in solutions with one partner, i.e. two students hand in one solution.

Sections Handed out to be handed in

Sheet 1: Repetition Topology 1

Solutions

Appendix A 16.10.2024 --

Sheet 2: Repetition Topology 2

Solutions

Appendix A 16.10.2024 22.10.2024

Sheet 3: Repetition Topology 3

Solutions

Appendix A 23.10.2024 29.10.2024

Sheet 4: Some known integrals

Solutions

Basics 30.10.2024 5.11.2024

Sheet 5: Semi-rings and sigma-fields

Solutions

Section 1.1, Videos 1, 2 6.11.2024 12.11.2024

Sheet 6: Set systems

Solutions

Sections 1.2, 1.3, 1.4, Videos 3, 4 13.11.2024 19.11.2024

Sheet 7: Set functions

Solutions

Sections 2.1, 2.2, Videos 5, 6 20.11.2024 26.11.2024

Sheet 8: Uniqueness and extension of set functions

Solutions

Section 2.3, Video 7 27.11.2024 3.12.2024

Sheet 9: Measures on $\mathbb R$

Solutions

Section 2.4, 2.5, 3.1, Video 8, 9 4.12.2024 10.12.2024

Sheet 10: The Lebesgue integral

Solutions

Section 3.2, 3.3, 3.4, Video 10, 11 11.12.2024 17.12.2024

Sheet 11: Basics of $L^p$-spaces

Solutions

Section 4.1, 4.2, Video 12 18.12.2024 7.1.2025

Sheet 12: $L^2$

Solutions

Section 4.3, Video 13 8.1.2025 14.1.2025

Sheet 13: Densities

Solutions

Section 4.4, Video 14 15.1.2025 21.1.2025

Sheet 14: Product spaces

Solutions

Section 5, Videos 15, 16, 17 22.1.2025 28.1.2025

1. Introduction

Some introductory remarks

Slides

2. Semi-rings and σ-fields

Covers Section 1.1

Slides

3. Generators and extensions

Covers Section 1.2, and includes some repetition in topology (Appendix A)

Slides

4. Dynkin systems and compact systems

Covers Sections 1.3 and 1.4

Slides

5. Set functions and outer measures

Covers Section 2.1

Slides

6. σ-additivity

Covers Section 1.2, and includes some repetition in topology (Appendix A)

Slides

7. Uniqueness and extension of set functions

Covers Section 2.3

Slides

8. Measures on ℝ and image measures

Covers Sections 2.4 and 2.5

Slides

9. Approximation of measurable functions

Slides

Covers Section 3.1

10. Defining the integral, and some properties

Slides

Covers Sections 3.2, 3.3

11. Convergence results

Covers Section 3.4

Slides

12. Basics of L^p -spaces

Covers Sections 4.1, 4.2

Slides

13. The space L^2

Covers Section 4.3

Slides

14. Theorem of Radon-Nikodým

Covers Section 4.4

Slides

15. Set systems on product spaces

Covers Sections 5.1, 5.2

Slides

16. Measures on product spaces

Covers Section 5.3, 5.4

Slides

17. Projective limits

Slides

Covers Section 5.5