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 Postoctoral Positions with Karim and Other Announcements!
 Jirka
 AviFest, AviStories and Amazing Cash Prizes.
 Polymath 10 post 6: The ErdosRado sunflower conjecture, and the Turan (4,3) problem: homological approaches.
 Polymath 10 Emergency Post 5: The ErdosSzemeredi Sunflower Conjecture is Now Proven.
 Mind Boggling: Following the work of Croot, Lev, and Pach, Jordan Ellenberg settled the cap set problem!
 More Math from Facebook
 The Erdős Szekeres polygon problem – Solved asymptotically by Andrew Suk.
 The Quantum Computer Puzzle @ Notices of the AMS
Top Posts & Pages
 The Erdős Szekeres polygon problem  Solved asymptotically by Andrew Suk.
 Believing that the Earth is Round When it Matters
 A Breakthrough by Maryna Viazovska Leading to the Long Awaited Solutions for the Densest Packing Problem in Dimensions 8 and 24
 Polymath 10 Emergency Post 5: The ErdosSzemeredi Sunflower Conjecture is Now Proven.
 Answer: Lord Kelvin, The Age of the Earth, and the Age of the Sun
 Extremal Combinatorics III: Some Basic Theorems
 Combinatorics, Mathematics, Academics, Polemics, ...
 The Ultimate Riddle
 The KadisonSinger Conjecture has beed Proved by Adam Marcus, Dan Spielman, and Nikhil Srivastava
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Category Archives: Combinatorics
From Oberwolfach: The Topological Tverberg Conjecture is False
The topological Tverberg conjecture (discussed in this post), a holy grail of topological combinatorics, was refuted! The threepage paper “Counterexamples to the topological Tverberg conjecture” by Florian Frick gives a brilliant proof that the conjecture is false. The proof is … Continue reading
Posted in Combinatorics, Conferences, Convexity, Updates
Tagged Florian Frick, Issac Mabillard, Uli Wagner
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Midrasha Mathematicae #18: In And Around Combinatorics
Tahl Nowik Update 3 (January 30): The midrasha ended today. Update 2 (January 28): additional videos are linked; Update 1 (January 23): Today we end the first week of the school. David Streurer and Peter Keevash completed … Continue reading
Posted in Combinatorics, Conferences, Updates
1 Comment
When Do a Few Colors Suffice?
When can we properly color the vertices of a graph with a few colors? This is a notoriously difficult problem. Things get a little better if we consider simultaneously a graph together with all its induced subgraphs. Recall that an … Continue reading
Coloring Simple Polytopes and Triangulations
Coloring Edgecoloring of simple polytopes One of the equivalent formulation of the fourcolor theorem asserts that: Theorem (4CT) : Every cubic bridgeless planar graph is 3edge colorable So we can color the edges by three colors such that every two … Continue reading
A lecture by Noga
Noga with Uri Feige among various other heroes A few weeks ago I devoted a post to the 240summit conference for Péter Frankl, Zoltán Füredi, Ervin Győri and János Pach, and today I will bring you the slides of Noga … Continue reading
Posted in Combinatorics, Conferences
Tagged Ankur Moitra, Benny Sudakov, Ervin Győri, János Pach, Noga Alon, Peter Frankl, Zoltán Füredi
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Jim Geelen, Bert Gerards, and Geoﬀ Whittle Solved Rota’s Conjecture on Matroids
Gian Carlo Rota Rota’s conjecture I just saw in the Notices of the AMS a paper by Geelen, Gerards, and Whittle where they announce and give a high level description of their recent proof of Rota’s conjecture. The 1970 conjecture asserts … Continue reading
Posted in Combinatorics, Open problems, Updates
Tagged Bert Gerards, Eric Katz, Geoﬀ Whittle, Gian Carlo Rota, Jim Geelen, June Huh, Matroids
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My Mathematical Dialogue with Jürgen Eckhoff
Jürgen Eckhoff, Ascona 1999 Jürgen Eckhoff is a German mathematician working in the areas of convexity and combinatorics. Our mathematical paths have met a remarkable number of times. We also met quite a few times in person since our first … Continue reading
Posted in Combinatorics, Convex polytopes, Open problems
Tagged Andy Frohmader, Helly's theorem, Jurgen Eckhoff, Nina Amenta, Noga Alon, Roy Meshulam
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Happy Birthday Richard Stanley!
This week we are celebrating in Cambridge MA , and elsewhere in the world, Richard Stanley’s birthday. For the last forty years, Richard has been one of the very few leading mathematicians in the area of combinatorics, and he found deep, profound, and … Continue reading
Influence, Threshold, and Noise
My dear friend Itai Benjamini told me that he won’t be able to make it to my Tuesday talk on influence, threshold, and noise, and asked if I already have the slides. So it occurred to me that perhaps … Continue reading