Symplectic Geometry Autumn 2023

Lecturer
Patricia Dietzsch
Organiser
Ana Žegarac
Time and location
Lectures:
Tuesday, 10:15 - 12:00 in HG D 1.2
Thursday, 08:15 - 10:00 in HG D 1.2
Exercise classes:
Friday, 12:15-13:00 in HG F 26.5
Course catalogue entry
401-3581-67L Symplectic Geometry

Content

This is an introductory course in symplectic geometry. We will cover some foundations of symplectic geometry (such as local theory, Lagrangian submanifolds and Hamiltonian flows). The last part of the course will be devoted to symplectic capacities and some rigidity results.

Prerequisites: Familiarity with differential geometry (in particular, differential forms and vector fields on manifolds) and with topology (including elementary algebraic topology) will be assumed.

Lectures

Handwritten lecture notes will be posted here (the password was emailed to all registered students on 19.09.2023).

Here is an errata for both, lecture notes and exercise sheets: Errata

Below we will post a tentative plan for the upcoming lectures.

DateContent
19.09. Motivation from physics, definition of a symplectic manifold, statements of highlights of the course (Gromov's Non-squeezing Theorem, Eliashberg–Gromov Theorem).
21.09. Arnol'd conjecture, Examples of symplectic manifolds (symplectic vector spaces, cotangent bundles, oriented surfaces, complex projective space)
26.09. Complex projective space, Symplectomorphisms, Hamiltonian diffeomorphisms
28.09. The group of Hamiltonian diffeomorphisms, autonomous Hamiltonians
3.10. Autonomous Hamiltonians, Moser stability
5.10. Darboux Theorem, equivalence of symplectic structures, linear complex structures
10.10. Linear complex structures, compatible triples
12.10. Compatible triples, almost complex structures
17.10. Integrable complex structures, symplectic capacities
19.10. Gromov width, rigidity of symplectomorphisms
24.10. Characterisation of symplectomorphisms via capacities
26.10. Characterisation of symplectomorphisms via capacities, Hofer-Zehnder capacity
31.10. Outline of proof of non-triviality of Hofer-Zehnder capacity, action functional
2.11. Action principle, action functional
7.11. Minimax principle, extending the action functional to a Hilbert space
9.11. Analysing the action functional
14.11. Different room: F26.3 Applying the minimax principle to the action functional
16.11. End of proof of non-triviality of Hofer-Zehnder capacity
21.11. Lagrangian submanifolds, the group of symplectomorphisms is locally path-connected
23.11. Lagrangian neighbourhood theorem, the group of symplectomorphisms is locally path-connected
28.11. Symplectic isotopies in exact symplectic manifolds
30.11. Flux homomorphism
5.12. Flux homomorphism and symplectic isotopies
7.12. Hamiltonian isotopies
12.12. (Non-)simplicity results, Calabi homomorphism
14.12. Q&A
19.12. Exam
21.12. A quick look into Floer homology

Exercises

A new exercise sheet will be posted every week on Tuesday or Wednesday. We will discuss the sheet in the exercise class on Friday, so it is recommended that you have a look at it beforehand.

The deadline for handing in solutions is 23:59 on Tuesday the following week. If you wish to hand in your solutions, please do so using the SAM Upload Tool. Corrections will be uploaded there a few days after the deadline.

If there are any issues with the SAM Upload Tool or if you notice any mistakes or typos in the exercises or in the solutions, please email Ana, the course organiser.

Exercise sheet Due by Solutions
Sheet 1 26.09. Solutions 1
Sheet 2 03.10. Solutions 2
Sheet 3 10.10. Solutions 3
Sheet 4 17.10. Solutions 4
Sheet 5 24.10. Solutions 5
Sheet 6 31.10. Solutions 6
Sheet 7 07.11. Solutions 7 (corrected version 14.12.23)
Sheet 8 14.11. Solutions 8
Sheet 9 21.11. Solutions 9
Sheet 10 28.11. Solutions 10
Sheet 11 05.12. Solutions 11
Sheet 12 12.12. Solutions 12
Sheet 13 - Solutions 13

Occasional notes related to what was discussed in exercise classes will be posted here (the password is same as the password for the lecture notes Polybox folder and was emailed to all registered students on 19.09.2923).

Exam

The exam will take place on Tuesday 19.12.2023. from 10:00 to 13:00 in HG D 1.2.

PhD students who wish to obtain credits for this course do not have to take the exam, but they have to hand in correct solutions to at least 50% of the exercises.

Literature