Colorful Combinatorics
Time and place: Monday 12:15-13:45 pm, Déli tömb 3-715, Pázmány Péter stny. 1/c.
Prerequisites:
Basic knowledge of combinatorics (Kombinatorika 1/Végmat 1)
Lecture notes (updated):
.pdf
Exam topics:
.pdf
The notes are based on less faulty books and lecture notes, notably:
Graham-Rothschild-Spencer: Ramsey Theory
Prömel: Ramsey Theory for Discrete Structures (producer: Steger)
Leader: Ramsey Theory https://www.dpmms.cam.ac.uk/~par31/notes/ramsey.pdf
de Zeeuw: A course in arithmetic Ramsey theory https://frankdezeeuw.wordpress.com/wp-content/uploads/2020/04/arithmeticramseytheory_20170506.pdf
Gasarch: Ramsey Theory and its "Applications" https://www.cs.umd.edu/~gasarch/COURSES/752/S25/index.html
Vitaly Bergelson, Florian K. Richter: Survey (NEW) https://arxiv.org/abs/2603.25922
Further recommended reading on related topics:
Lovász: Topological Methods in Combinatorics
Soifer: The new mathematical coloring book Mathematics of coloring and the colorful life of its creators
Gasarch's collection: https://www.cs.umd.edu/~gasarch/COURSES/752/S25/ramseybooks.html
1. class (15 sept): Sperner's lemma, Monsky's theorem, Envy-free division
2. class (22 sept): Tucker's lemma, Ky Fan's lemma, Necklace splitting, Kneser graphs
3. class (29 sept): Graph complexes, Hypergraph Ramsey upper bound
4. class (6 oct): Hypergraph Ramsey lower bound (Stepping-up lemma), some extra Ramsey stuff
5. class (13 oct): Erdős-Szekereses, abstract cup-cap, Schur's theorem, Hilbert's cube lemma
6. class (20 oct): van der Waerden's theorem
Fall break (27 oct): no class
7. class (3 nov): Hales-Jewett theorem, canonical vdW, Shelah's proof of HJ
8. class (10 nov): Rado's theorems except for hardest proof
9. class (17 nov): Missing proof of Rado's theorem with Deuber's theorem
10. class (24 nov): Extra Rado-related, Graham--Rothschild (without proof), Euclidean Ramsey product theorem
11. class (1 dec): Spherical and subtransitive sets in Euclidean Ramsey theory
12. class (8 dec): Cyclic transitivity implies Ramsey
We didn't have time for the below, previously planned topics that start with c:
canonical Ramsey, chi-boundedness, combinatorial discrepancy