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 AviFest, AviStories and Amazing Cash Prizes.
 Polymath 10 post 6: The ErdosRado sunflower conjecture, and the Turan (4,3) problem: homological approaches.
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 Mind Boggling: Following the work of Croot, Lev, and Pach, Jordan Ellenberg settled the cap set problem!
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 The Erdős Szekeres polygon problem – Solved asymptotically by Andrew Suk.
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 AviFest, AviStories and Amazing Cash Prizes.
 A Breakthrough by Maryna Viazovska Leading to the Long Awaited Solutions for the Densest Packing Problem in Dimensions 8 and 24
 Seven Problems Around Tverberg's Theorem
 Polymath 10 post 6: The ErdosRado sunflower conjecture, and the Turan (4,3) problem: homological approaches.
 Answer: Lord Kelvin, The Age of the Earth, and the Age of the Sun
 The Erdős Szekeres polygon problem  Solved asymptotically by Andrew Suk.
 Believing that the Earth is Round When it Matters
 Polymath10: The Erdos Rado Delta System Conjecture
 Analysis of Boolean Functions
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Monthly Archives: September 2008
Extremal Combinatorics III: Some Basic Theorems
. Shattering Let us return to extremal problems for families of sets and describe several basic theorems and basic open problems. In the next part we will discuss a nice proof technique called “shifting” or “compression.” The SauerShelah (Perles VapnikChervonenkis) Lemma: (Here we write .) … Continue reading
New Haven (mainly pictures)
] Yale, New Haven I am back in New Haven which have become my home away from home in the last five years. Cappuccino’S and more – Cedar cross Congress, New Haven. Not only that this name is similar … Continue reading
Posted in Uncategorized
Tagged New Haven, Three dimensional electron microscopy, Yale, Yoel Shkolinsky
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Annotating Kimmo Eriksson’s Poem
“Start counting her NUMBER OF FACES,” Kimmo Eriksson, Brush up your Björner (2008). The time is right to annotate Kimmo Eriksson’s memorable poem: 1. What are Chip firing games? Many women will find it admirable if you tell her she … Continue reading
A Diameter Problem (5)
6. First subexponential bounds. Proposition 1: How to prove it: This is easy to prove: Given two sets and in our family , we first find a path of the form where, and . We let with and consider the family … Continue reading
Diameter Problem (4)
Let us consider another strategy to deal with our diameter problem. Let us try to associate other graphs to our family of sets. Recall that we consider a family of subsets of size of the set . Let us now associate … Continue reading
Diameter Problem (3)
3. What we will do in this post and and in future posts We will now try all sorts of ideas to give good upper bounds for the abstract diameter problem that we described. As we explained, such bounds apply … Continue reading
Posted in Combinatorics, Convex polytopes, Open problems
Tagged Hirsch conjecture, Linear programming, Quasiautomated proofs
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Oded
I just heard the terrible news that Oded Schramm was killed in a hiking accident. Oded was hiking on Guye Peak near Snoqualmie Pass near Seattle. This is a terrible loss to Oded’s family, and our hearts and thoughts are … Continue reading
The Prisoner’s Dilemma, Sympathy, and Yaari’s Challenge
Correlation and Cooperation In our spring school devoted to Arrow’s economics, Menahem Yaari gave a talk entitled “correlation and cooperation.” It was about games as a model of people’s behavior, and Yaari made the following points: It is an empirical fact … Continue reading
Posted in Economics, Games, Philosophy, Rationality
Tagged Cooperation, Correlation, Prisoner dilemma
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