Reading seminar

Nincs elégtétel, ha túl könnyű a tétel. (Erdős Pál)

Where and when

We typically we will meet at the CS Institute (Ústav informatiky, Pod Vodárenskou věží 2; directions)

If we broadcast on ZOOM, it is in the room https://cesnet.zoom.us/j/3906355031 (with waiting room)

At the CS Institute, the default location is room 318, backup rooms are 107 or 419, see the schedule before coming.

You are welcome in the lecture room for tea and biscuits 15 minutes before the start.

Programme

2022

Friday July 1 in 318, 10:00-11:00, Tomas surveying thresholds for random sets

Friday June 24 in 318 (and on Zoom), 10:00-11:00, Pedro talking about A proof of the Kahn-Kalai conjecture

Monday February 21 in 419 (and on Zoom), 10:00-11:30, Honza H. talking about Graph norms. (Graph norms are a useful new tool for handling many problems extremal graph(on) theory. I will explain some basics. I will assume that people know what a graphon is.)

2021

Friday December 17 in 318 (and on Zoom), 9:30-11:00, Matas on Gärtner-Ellis theorem

Tuesday December 14 in 419 (and on Zoom) 10:00-11:30, Tomas talking anticoncentration and the perfect graph theorem

Friday December 10 in 419 (and on Zoom), 9:30-11:00, Matas on Cramér's theorem: lower bound and extension to higher dimensions

Friday December 3, 9:30-11:00 in 419 (and on Zoom), Tomas completing a proof from Chatterjee and Varadhan; Matas on Cramér's theorem

Friday November 26, 9:30-11:00 in 318 (and on Zoom), Tomas continuing on the paper of Chatterjee and Varadhan

Friday November 19, 9:30-11:00 in 318 (and on Zoom), Cancelled due to illness: Tomas continuing on the paper of Chatterjee and Varadhan

Friday 12: no seminar (book event)

Friday November 5, 10:00-11:30 in 419 (and on Zoom), Tomas presenting The large deviation principle for the Erdős-Rényi random graph by Chatterjee and Varadhan

October 29: no seminar (schoolchildren's holiday)

Friday October 22 in 318, 10:00-11:30 (and on Zoom), Pedro continuing on Combinatorial anti-concentration inequalities, with applications.

Friday October 15 in 419, 10:00-11:00 (and on Zoom), Honza H. continuing on Linear cover time is exponentially unlikely

Friday October 8 in 419, 10:00-11:30 (and on Zoom), Pedro presenting Combinatorial anti-concentration inequalities, with applications by Jacob Fox, Matthew Kwan, and Lisa Sauermann.

Friday October 1 in 318, 10:00-11:00 (and on Zoom), Honza H. presenting Linear cover time is exponentially unlikely by Quentin Dubroff and Jeff Kahn.

Friday September 17 in 318, 10:00-11:00 (cancelled), Pedro

Tuesday June 29 in 318 (and on Zoom - unusually at https://cesnet.zoom.us/my/honzahladky) at 10:30, Honza will read Section 2.1 Combinatorial Techniques for Finite Alphabets from book Large Deviations: Techniques and Applications by A. Dembo, O. Zeitouni

Thursday June 17 in 318 (and Zoom) at 10:30-11:30, Tomas will continue what is left from the last talk

Friday June 11 in 318 (and Zoom) at 10:30-11:30, Tomas will talk about Shearer's inequality and how it is used in Janson-Oleszkiewicz-Ruciński paper

Friday June 4, at CS Institute (broadcast on Zoom) Pedro will present Harel-Mousset-Samotij upper tail proof for triangle count.

Friday May 28 on Zoom, 10:30-11:30, Matas continues on Janson, Oleszkiewicz and Ruciński. Notes

Friday May 21 on Zoom, 10:30-11:30, Matas talking about the upper tail problem for subgraph counts in G(n,p), focusing on Janson, Oleszkiewicz and Ruciński 2004. Notes

2020

Thursday Mar 12 at CS Institute, 10:00-13:45, Diana continuing about packing degenerate graphs, CANCELLED

Friday Mar 6 at Maths Institute, Frederik taling about the proof of Ringel's Conjecture

Feb 27, no seminar

Friday Feb 21 at CS Institute, 10:00-11:30, CANCELLED

Thursday Feb 13 at Maths Institute, 13:01-14.31, Honza talking about Graceful tree labelling conjecture

Thursday Feb 6 at CS Institute, 13:00-14:30, Diana talking about packing degenerate graphs.

Thursday Jan 30 at CS Institute, 13:00-14:30, Diana giving an introductory talk about packing

Thursday Jan 23 at CS Institute, 14:00-15:30, Matas reading about concentration inequalities

2019

Thursday Oct 24 at Matematický ustav (Žitná 25), Modra poslucharna, 13:00-14:30, Honza Hladký reading Davies, Jenssen, Perkins, Roberts: Independent Sets, Matchings, and Occupancy Fractions

Thursday Nov 7 at Matematický ustav (Žitná 25), Modra poslucharna, 14:00-15:30, Honza Hladký reading about the Ising model from these lecture notes.

Thursday Nov 14 at Ústav informatiky (Pod vodárenskou věží 2; directions), Meeting room 419, 13:00-14:30, Frederik reading kissing numbers

Thursday Nov 21 at Matematický ústav (Žitná 25), Konírna, 13:00-14:30, Nicolás reading about the Matching measure

Thursday Nov 28 at Matematický ústav (Žitná 25), Konírna, 13:00-14:30, Hanka reading Matchings in B-S convergent sequences

Thursday Dec 05 at Matematický ústav (Žitná 25), Konírna, 13:00-14:30, Christos reading Widom-Rowlinson model

Thursday Dec 12 at Matematický ústav (Žitná 25), Konírna, 13:00-14:30, Matas reading about the Bethe lattice

Suggested papers to be read (to be extended)

2021

Upper tail:

Large deviations, general theory:

  • Section 2.1 Combinatorial Techniques for Finite Alphabets from book Large Deviations Techniques and Applications by A. Dembo, O. Zeitouni (I think this is a kind of introduction explaining what "entropy" is in the context of large deviations).

Subgraph count distribution:

Other:

2020 spring

Designs:

Minimalist designs, Ben Barber, Stefan Glock, Daniela Kühn, Allan Lo, Richard Montgomery, Deryk Osthus (already contains the main ideas of the "The existence of designs via iterative absorption")

Coloured and directed designs, Peter Keevash (Very hard)

The existence of designs via iterative absorption, Stefan Glock, Daniela Kühn, Allan Lo, Deryk Osthus

Decomposition:

A short proof of the blow-up lemma for approximate decompositions Stefan Ehard and Felix Joos (contains a considerably shorter proof of the main result of the paper by Kim, Kühn, Osthus, Tyomkyn (26 vs. 70 pages))

A blow-up lemma for approximate decompositions, Jaehoon Kim, Daniela Kühn, Deryk Osthus, Mykhaylo Tyomkyn

Packing degenerate graphs, Peter Allen, Julia Böttcher, Jan Hladký, Diana Piguet

Embedding rainbow trees with applications to graph labelling and decomposition, Richard Montgomery, Alexey Pokrovskiy, Benny Sudakov, reservation for Frederik

Resolution of the Oberwolfach problem, Stefan Glock, Felix Joos, Jaehoon Kim, Daniela Kühn, Deryk Osthus

Optimal packings of bounded degree trees, Felix Joos, Jaehoon Kim, Daniela Kühn, Deryk Osthus (the blow-up lemma for approximate decompositions is a main tool in this paper)

A bandwidth theorem for approximate decompositions, P. Condon, Jaehoon Kim, D. Kühn, D. Osthus (the blow-up lemma for approximate decomposition was also used as the main tool; the result of this paper that was the main tool used in the "Oberwolfach problem" paper)

Packing minor-closed families of graphs into complete graphs, Silvia Messuti, Vojtěch Rödl, Mathias Schacht (Easier), reservation for Hanka

Packing trees of unbounded degrees in random graphs, Asaf Ferber, Wojciech Samotij

Packing spanning graphs from separable families, Asaf Ferber, Choongbum Lee, Frank Mousset (Easier)

A proof of Ringel's Conjecture, Richard Montgomery, Alexey Pokrovskiy, Benny Sudakov, reservation for Frederik

Diana's comments "Very hard"and "Easier" apply to those she has read, so no comment means: "I have no idea"

2019 autumn

Graphs and polynomials:

a survey by Will Perkins: here

Hard constraints and the Bethe lattice: adventures at the interface of combinatorics and statistical physics (note that Bethe lattice is infinite d-regular tree, a relatively pleasant object)

Matchings in Benjamini–Schramm convergent graph sequences, reservation for Hanka

On kissing numbers and spherical codes in high dimensions, reservation for Frederik

Matching measure, Benjamini-Schramm convergence and the monomer-dimer free energy, reservation for Nicolas

Benjamini–Schramm continuity of root moments of graph polynomials, this one is perhaps difficult if you are not strong in algebra

The Widom–Rowlinson model, the hard-core model and the extremality of the complete graph, reservation for Christos

this book by Mézard and Montanari

Upper tails and independence polynomials in random graphs - rather advanced topic in random graphs, may be a topic for the next season