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 Peter Cameron: Doing research
 To cheer you up in difficult times 18: Beautiful drawings by Neta Kalai for my book: “Gina Says”
 Amazing: Simpler and more general proofs for the gtheorem by Stavros Argyrios Papadakis and Vasiliki Petrotou, and by Karim Adiprasito, Stavros Argyrios Papadakis, and Vasiliki Petrotou.
 Igor Pak: What if they are all wrong?
 To cheer you up in difficult times 17: Amazing! The ErdősFaberLovász conjecture (for large n) was proved by Dong Yeap Kang, Tom Kelly, Daniela Kühn, Abhishek Methuku, and Deryk Osthus!
 Open problem session of HUJICOMBSEM: Problem #5, Gil Kalai – the 3ᵈ problem
 To cheer you up in difficult times 16: Optimism, two quotes
 The Argument Against Quantum Computers – A Very Short Introduction
 Open problem session of HUJICOMBSEM: Problem #4, Eitan Bachmat: Weighted Statistics for Permutations
Top Posts & Pages
 Peter Cameron: Doing research
 TYI 30: Expected number of Dice throws
 Amazing: Simpler and more general proofs for the gtheorem by Stavros Argyrios Papadakis and Vasiliki Petrotou, and by Karim Adiprasito, Stavros Argyrios Papadakis, and Vasiliki Petrotou.
 Igor Pak: What if they are all wrong?
 Chomskian Linguistics
 The Argument Against Quantum Computers  A Very Short Introduction
 Answer: Lord Kelvin, The Age of the Earth, and the Age of the Sun
 To cheer you up in difficult times 18: Beautiful drawings by Neta Kalai for my book: "Gina Says"
 Dan Romik on the Riemann zeta function
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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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