WiSe 23/24: Algebraic Topology I
Lectures: Tuesday 08-10 and Thursday 10-12 in M101
Exercises: Friday 12-14 in M101
Algebraic topology studies topological spaces by means of algebraic invariants (groups, vector spaces, etc.), which allow us to reduce questions in topology to questions in algebra. Algebraic topology has many applications, both in theoretical and in applied mathematics. Nowadays, a basic knowledge of algebraic topology is essential in most other fields of pure mathematics, including analysis, algebraic geometry, and number theory. In applied mathematics, topological data analysis is a relatively new field that relies heavily on tools from algebraic topology.
In this first course on algebraic topology, we will study in depth two important invariants of a topological space: its fundamental group and its (co)homology groups. We will also see how to use these algebraic invariants to answer some interesting topological questions.
Topics covered in this course include:
- Covering spaces and the fundamental group
- Simplicial sets and singular (co)homology
- CW complexes and cellular (co)homology
- Miscellaneous applications (the fundamental theorem of algebra, Brouwer’s fixed point theorem and invariance of domain, the hedgehog theorem, etc.)
Exercises
- Sheet 1 (due 27.10)
- Sheet 2 (due 03.11)
- Sheet 3 (due 10.11)
- Sheet 4 (due 17.11)
- Sheet 5 (due 24.11)
- Sheet 6 (due 01.12)
- Sheet 7 (due 08.12)
- Sheet 8 (due 15.12)
- Sheet 9 (due 22.12)
- Sheet 10 (due 12.01)
- Sheet 11 (due 19.01)
- Sheet 12 (due 26.01)
- Sheet 13 (due 02.01)
Lecture notes
From WiSe 20/21:
- §1. Homotopy
- Lecture 1
- Lecture 2
- §2. The fundamental groupoid
- Lecture 3
- Lecture 4
- §3. The Seifert–van Kampen theorem
- Lecture 5
- Lecture 6
- §4. Covering spaces
- Lecture 7
- Lecture 8
- Lecture 9
- Lecture 10
- §5. Simplicial sets
- Lecture 11
- Lecture 12
- Lecture 13
- §6. Singular homology
- Lecture 14
- Lecture 15
- Lecture 16
- Lecture 17
- Lecture 18
- §7. Cellular homology
- Lecture 19
- Lecture 20
- Lecture 21
- §8. Künneth, universal coefficients, cohomology
- Lecture 22
- Lecture 23
- Lecture 24
- Lecture 25
- Lecture 26
References
- A. Hatcher, Algebraic Topology, 2001
- C. Löh, Algebraic Topology, An introductory course, Wintersemester 2021/22
- W. Lück, Algebraische Topologie: Homologie une Mannigfaltigkeiten, 2005
- R. Brown, Topology and Groupoids, 2006
- T. tom Dieck, Algebraic Topology, 2008