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 Alexander A. Gaifullin: Many 27vertex Triangulations of Manifolds Like the Octonionic Projective Plane (Not Even One Was Known Before).
 Answer to Test Your Intuition 50: Detecting a Deviator
 To cheer you up in difficult times 36: The Immense Joy of Fake Reverse Parking
 Ordinary computers can beat Google’s quantum computer after all
 Test Your Intuition 50. TwoPlayer Random Walk; Can You Detect Who Did Not Follow the Rules?
 ICM 2022. Kevin Buzzard: The Rise of Formalism in Mathematics
 ICM 2022: Langlands Day
 ICM 2022 awarding ceremonies (1)
 ICM 2022 Virtual Program, Live events, and Dynamics Week in Jerusalem
Top Posts & Pages
 How Large can a Spherical Set Without Two Orthogonal Vectors Be?
 ICM 2022: Langlands Day
 Amazing: Hao Huang Proved the Sensitivity Conjecture!
 ICM 2022. Kevin Buzzard: The Rise of Formalism in Mathematics
 Amazing: Karim Adiprasito proved the gconjecture for spheres!
 Raigorodskii's Theorem: Follow Up on Subsets of the Sphere without a Pair of Orthogonal Vectors
 Alexander A. Gaifullin: Many 27vertex Triangulations of Manifolds Like the Octonionic Projective Plane (Not Even One Was Known Before).
 Answer to Test Your Intuition 50: Detecting a Deviator
 Impagliazzo's Multiverse
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Monthly Archives: November 2020
Recent progress on high dimensional TuranType problems by Andrey Kupavskii, Alexandr Polyanskii, István Tomon, and Dmitriy Zakharov and by Jason Long, Bhargav Narayanan, and Corrine Yap.
The extremal number for surfaces Andrey Kupavskii, Alexandr Polyanskii, István Tomon, Dmitriy Zakharov: The extremal number of surfaces Abstract: In 1973, Brown, Erdős and Sós proved that if is a 3uniform hypergraph on vertices which contains no triangulation of the sphere, then … Continue reading
Open problem session of HUJICOMBSEM: Problem #1, Nati Linial – Turan type theorems for simplicial complexes.
On November, 2020 we had a very nice open problem session in our weekly combinatorics seminar at HUJI. So I thought to have a series of posts to describe you the problems presented there. This is the first post in … Continue reading
Péter Pál Pach and Richárd Palincza: a Glimpse Beyond the Horizon
Prologue Consider the following problems: P3: What is the maximum density of a set A in without a 3term AP? (AP=arithmetic progression.) This is the celebrated Cap Set problem and we reported here in 2016 the breakthrough results by … Continue reading
Posted in Combinatorics, Geometry, Number theory, Open problems
Tagged Péter Pál Pach, Richárd Palincza
9 Comments
To cheer you up 14: Hong Liu and Richard Montgomery solved the Erdős and Hajnal’s odd cycle problem
The news: In 1981, Paul Erdős and András Hajnal asked whether the sum of the reciprocals of the odd cycle lengths in a graph with infinite chromatic number is necessarily infinite. Hong Liu and Richard Montgomery have just proved that … Continue reading
Posted in Combinatorics
Tagged András Hajnal, Carsten Thomassen, Hong Liu, Paul Erdos, Richard Montgomry
7 Comments
To cheer you up in difficult times 13: Triangulating real projective spaces with subexponentially many vertices
Wolfgang Kühnel Today I want to talk about a new result in a newly arXived paper: A subexponential size by Karim Adiprasito, Sergey Avvakumov, and Roman Karasev. Sergey Avvakumov gave about it a great zoom seminar talk about the result … Continue reading
Posted in Algebra, Combinatorics, Geometry
Tagged Karim Adiprasito, Roman Karasev, Sergey Avvakumov, Wolfgang Kuhnel
4 Comments
Benjamini and Mossel’s 2000 Account: Sensitivity of Voting Schemes to Mistakes and Manipulations
Here is a popular account by Itai Benjamini and Elchanan Mossel from 2000 written shortly after the 2000 US presidential election. Elchanan and Itai kindly agreed that I will publish it here, for the first time, 20 years later! I … Continue reading
Posted in Combinatorics, Games, Probability, Rationality
Tagged Elchanan Mossel, Itai Benjamini
6 Comments