Prof. Alexander F. Ritter
Associate Professor, University of Oxford



In addition to the notes below, there are also notes from a 2024 course on Morse Homology at Oxford, which are less formal, and possibly more helpful to graduate students: Morse Homology (TCC Graduate course) : Lecture notes here.


⋄ CAMBRIDGE PART III COURSE ON MORSE HOMOLOGY (LENT TERM 2011)

LECTURE NOTES

I would be very grateful for your feedback in the form of typos, suggestions or mistakes you found, because these notes will be published as a book.

My contact details: find the contacts here

Combined PDF of all 24 Lectures and Homeworks: all Lectures and homeworks in one package

Combined PDF of all 24 Lectures (no homeworks)

Combined PDF of all Homeworks

Lecture 1: (PDF)(PS) Morse functions, topology of sublevel sets, Morse homology, number of critical points of a generic function, geometry vs functional analysis, Poincare duality via Morse homology

Lecture 2: (PDF)(PS) connections, parallel transport, Levi-Civita, geodesics, exp map, diffeomorphisms, regular maps

Lecture 3: (PDF)(PS) Sard's thm, transversality, intersection numbers, stability, embedding thm, tubular nbhd thm

Lecture 4: (PDF)(PS) Parametric transversality, perturbing a map to make it transverse to a submfd, zeros of sections, Morse functions, properties of Morse functions.

Lecture 5: (PDF)(PS) Banach spaces, C^{infinity} is not Banach, Banach manifolds, Inverse/implicit fn thm, why Fredholm maps

Lecture 6: (PDF)(PS) Fredholm operators, Sard-Smale theorem, zeros of Fredholm sections

Lecture 7: (PDF)(PS) Flowlines, properties of negative gradient flows, energy estimates, cobordisms, h-cobordism thm

Lecture 8: (PDF)(PS) handle attachments, topology of sublevel sets, stable and unstable mfds,

Lecture 9: (PDF)(PS) Morse-Smale metrics, Morse homology = cellular homology for self-indexing Morse functions,

Lecture 10: (PDF)(PS) Moduli spaces, overview: Floer homology, symplectic homology, Lagrangian Floer homology, Fukaya category and mirror symmetry, Heegaard-Floer homology, Instanton homology, Seiberg-Witten homology

Lecture 11: (PDF)(PS) Sobolev spaces, Sobolev embedding thm, Rellich compactness thm, Sobolev on manifolds

Lecture 12: (PDF)(PS) Banach space setup for the transversality thm: checking the spaces are Banach mfds

Lecture 13: (PDF)(PS) showing the section is C^k, proof of the transversality thm

Lecture 14: (PDF)(PS) reducing to the local setup d/ds + A_s, proof it is Fredholm

Lecture 15: (PDF)(PS) formal adjoints, index calculation for d/ds + A_s

Lecture 16: (PDF)(PS) spectral flow for d/ds + A_s with A_s converging to hyperbolic matrices, homotopy invariance of the index

Lecture 17: (PDF)(PS) compactness of the moduli spaces up to breaking

Lecture 18: (PDF)(PS) gluing theorem

Lecture 19: (PDF)(PS) definition of Morse homology, invariance theorem

Lecture 20: (PDF)(PS) invariance of Morse homology under changing Morse function and Riemannian metric

Lecture 21: (PDF)(PS) Poincare' duality, Kunneth Theorem, Morse inequalities, Intersection/cup product via Morse-graph flows

Lecture 22 and 23: (PDF)(PS) (Non-examinable) Spectral sequences, Leray-Serre spectral sequence in Morse homology

Lecture 24: (PDF)(PS) (Non-examinable) Morse-Bott homology, spectral sequence for Morse-Bott theory

(Lecture 24 was the last lecture)

Course Description: description of the Part III course

Syllabus: Initial Syllabus of the course I handed out

Exam Guide: What the key topics are, what is examinable, and what isn't
___________________________

Prof. Alexander F. Ritter. Contact me.
Associate Professor in Geometry, Mathematical Institute, Oxford.
The Roger Penrose Fellow and Tutor, Wadham College, Oxford.