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 Combinatorics and More – Greatest Hits
 Ilan and me
 The Simplex, the Cyclic polytope, the Positroidron, the Amplituhedron, and Beyond
 From Oberwolfach: The Topological Tverberg Conjecture is False
 Midrasha Mathematicae #18: In And Around Combinatorics
 Quantum computing: achievable reality or unrealistic dream
 A Historical Picture Taken by Nimrod Megiddo
 Scott Triumphs* at the Shtetl
 Amy Triumphs* at the Shtetl
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 Combinatorics and More  Greatest Hits
 Academic Degrees and Sex
 The KadisonSinger Conjecture has beed Proved by Adam Marcus, Dan Spielman, and Nikhil Srivastava
 Combinatorics, Mathematics, Academics, Polemics, ...
 The AC0 Prime Number Conjecture
 From Oberwolfach: The Topological Tverberg Conjecture is False
 Ziegler´s Lecture on the Associahedron
 The Simplex, the Cyclic polytope, the Positroidron, the Amplituhedron, and Beyond
 Five Open Problems Regarding Convex Polytopes
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Author Archives: Gil Kalai
NatiFest is Coming
The conference Poster as designed by Rotem Linial A conference celebrating Nati Linial’s 60th birthday will take place in Jerusalem December 1618. Here is the conference’s webpage. To celebrate the event, I will reblog my very early 2008 post “Nati’s … Continue reading
Posted in Combinatorics, Computer Science and Optimization, Conferences, Updates
Tagged Nati Linial
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More around Borsuk
Piotr Achinger told me two things abour Karol Borsuk: From Wikipedea: Dunce hat Folding. The blue hole is only for better view Borsuk trumpet is another name for the contractible noncollapsible space commonly called also the “dunce hat“. (See … Continue reading
Analysis of Boolean Functions – Week 7
Lecture 11 The Cap Set problem We presented Meshulam’s bound for the maximum number of elements in a subset A of not containing a triple x,y,x of distinct elements whose sum is 0. The theorem is analogous to Roth’s theorem … Continue reading
Posted in Combinatorics, Computer Science and Optimization, Teaching
Tagged Cap set problem, Codes, Linearity testing
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Analysis of Boolean Functions week 5 and 6
Lecture 7 First passage percolation 1) Models of percolation. We talked about percolation introduced by Broadbent and Hammersley in 1957. The basic model is a model of random subgraphs of a grid in ndimensional space. (Other graphs were considered later as … Continue reading
Posted in Combinatorics, Computer Science and Optimization, Probability, Teaching
Tagged Arrow's theorem, Percolation
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Real Analysis Introductory Minicourses at Simons Institute
The Real Analysis ‘Boot Camp’ included three excellent minicourses. Inapproximability of Constraint Satisfaction Problems (5 lectures) Johan Håstad (KTH Royal Institute of Technology) (Lecture I, Lecture II, Lecture III, Lecture IV, Lecture V) Unlike more traditional ‘boot camps’ Johan rewarded answers and questions … Continue reading
Analysis of Boolean Functions – week 4
Lecture 6 Last week we discussed two applications of the FourierWalsh plus hypercontractivity method and in this lecture we will discuss one additional application: The lecture was based on a 5pages paper by Ehud Friedgut and Jeff Kahn: On the number … Continue reading
Polymath 8 – a Success!
Yitang Zhang Update (July 22, ’14). The polymath8b paper “Variants of the Selberg sieve, and bounded intervals containing many primes“, is now on the arXiv. See also this post on Terry Tao’s blog. Since the last update, we also had here … Continue reading
Analysis of Boolean Functions – Week 3
Lecture 4 In the third week we moved directly to the course’s “punchline” – the use of FourierWalsh expansion of Boolean functions and the use of Hypercontractivity. Before that we started with a very nice discrete isoperimetric question on a … Continue reading
Richard Stanley: How the Proof of the Upper Bound Theorem (for spheres) was Found
The upper bound theorem asserts that among all ddimensional polytopes with n vertices, the cyclic polytope maximizes the number of facets (and kfaces for every k). It was proved by McMullen for polytopes in 1970, and by Stanley for general triangulations … Continue reading
Simons@UCBerkeley
Raghu Meka talking at the workshop I spend the semester in Berkeley at the newly founded Simons Institute for the Theory of Computing. The first two programs demonstrate well the scope of the center and why it is needed. One program … Continue reading
Posted in Conferences, Updates
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