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 Ringel Conjecture, Solved! Congratulations to Richard Montgomery, Alexey Pokrovskiy, and Benny Sudakov
 Test your intuition 43: Distribution According to Areas in Top Departments.
 Two talks at HUJI: on the “infamous lower tail” and TOMORROW on recent advances in combinatorics
 Amazing: Zhengfeng Ji, Anand Natarajan, Thomas Vidick, John Wright, and Henry Yuen proved that MIP* = RE and thus disproved Connes 1976 Embedding Conjecture, and provided a negative answer to Tsirelson’s problem.
 Do Not Miss: Abel in Jerusalem, Sunday, January 12, 2020
 The BrownErdősSós 1973 Conjecture
 Tomorrow: Boolean functions day at the TAU theory fest
 The Google Quantum Supremacy Demo and the Jerusalem HQCA debate.
 Four Great Numberphile Graph Theory Videos
Top Posts & Pages
 Ringel Conjecture, Solved! Congratulations to Richard Montgomery, Alexey Pokrovskiy, and Benny Sudakov
 Test your intuition 43: Distribution According to Areas in Top Departments.
 Amazing: Zhengfeng Ji, Anand Natarajan, Thomas Vidick, John Wright, and Henry Yuen proved that MIP* = RE and thus disproved Connes 1976 Embedding Conjecture, and provided a negative answer to Tsirelson's problem.
 TYI 30: Expected number of Dice throws
 Amazing: Peter Keevash Constructed General Steiner Systems and Designs
 R(5,5) ≤ 48
 A sensation in the morning news  Yaroslav Shitov: Counterexamples to Hedetniemi's conjecture.
 Answer: Lord Kelvin, The Age of the Earth, and the Age of the Sun
 Elchanan Mossel's Amazing Dice Paradox (your answers to TYI 30)
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Monthly Archives: March 2019
Is it Legitimate/Ethical for Google to close Google+?
Update April 2, 2019: the links below are not working anymore. Google Plus is a nice social platform with tens of millions participants. I found it especially nice for scientific posts, e.g. by John Baez, Moshe Vardi, or about symplectic … Continue reading
10 Milestones in the History of Mathematics according to Nati and Me
Breaking news: David Harvey and Joris Van Der Hoeven. Integer multiplication in time O(nlogn). 2019. (I heard about it from Yoni Rozenshein on FB (חפירות על מתמטיקה); update GLL post. ) _____ Update: There were many interesting comments here and … Continue reading
TYI38 Lior Kalai: Monty Hall Meets Survivor
For breaking news, scroll down. Lior Kalai: Survivor Meets the Monty Hall Puzzle We start with the classical question and go on with a new version contributed by my son Lior. Update: A few brief comments on the original problem … Continue reading
Posted in Probability, Riddles, Test your intuition
Tagged Karen Uhlenbeck, Lior Kalai, Monty Hall problem, Survivor
3 Comments
News on Fractional Helly, Colorful Helly, and Radon
My 1983 Ph D thesis was on Hellytype theorems which is an exciting part of discrete geometry and, in the last two decades, I have had an ongoing research project with Roy Meshulam on topological Hellytype theorems. The subject found … Continue reading
8866128975287528³+(8778405442862239)³+(2736111468807040)³
Update: The result was achieved by Andrew Booker from Bristol. Here is the preprint Cracking the problem with 33. It is a notoriously difficult open problem which integers can be written as the sum of three integer cubes. Such integers … Continue reading
Test Your Intuition (or simply guess) 37: Arithmetic Progressions for Brownian Motion in Space
Consider a Brownian motion in three dimensional space. What is the largest number of points on the path described by the motion which form an arithmetic progression? (Namely, , so that all are equal.) A 2D picture; In … Continue reading
Test Your Intuition (or knowledge, or programming skills) 36
How much is The product ranges over all primes. In other words, Just heard it from Avinoam Mann.
Bob Sedgewick’s Free Online Courses on Analysis of Algorithms and Analytic Combinatorics.
Philippe Flajolet 19482011 I am happy to forward the announcement on two free online courses (Mooks) by Bob Sedgewick Analysis of Algorithms and Analytic Combinatorics. Analysis of Algorithms page provides access to online lectures, lecture slides, and assignments for … Continue reading