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 Let me tell you about three of my recent papers
 Mathematical news to cheer you up
 To Cheer You Up in Difficult Times 28: Math On the Beach (Alef’s Corner)
 To cheer you up in difficult times 27: A major recent “Lean” proof verification
 To cheer you up in difficult times 26: Two reallife lectures yesterday at the Technion
 To Cheer You Up in Difficult times 24: Borodin’s colouring conjecture!
 To cheer you up in difficult times 25: some mathematical news! (Part 2)
 To cheer you up in difficult times 23: the original handwritten slides of Terry Tao’s 2015 Einstein Lecture in Jerusalem
 Alef Corner: ICM2022
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 Let me tell you about three of my recent papers
 Mathematical news to cheer you up
 To cheer you up in difficult times 27: A major recent "Lean" proof verification
 The Argument Against Quantum Computers  A Very Short Introduction
 TYI 30: Expected number of Dice throws
 A sensation in the morning news  Yaroslav Shitov: Counterexamples to Hedetniemi's conjecture.
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 Around Borsuk's Conjecture 1: Some Problems
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Category Archives: Convexity
To cheer you up in difficult times 22: some mathematical news! (Part 1)
To cheer you up, in these difficult times, here are (in two parts) some mathematical news that I heard in personal communications or on social media. (Maybe I will write later, in more details, about few of them that are … Continue reading
Posted in Combinatorics, Convex polytopes, Convexity, Geometry
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Cheerful News in Difficult Times: The Abel Prize is Awarded to László Lovász and Avi Wigderson
The Abel Prize was awarded earlier today to László Lovász and Avi Wigderson “for their foundational contributions to theoretical computer science and discrete mathematics, and their leading role in shaping them into central fields of modern mathematics.” Congratulations to Laci … Continue reading
To Cheer You Up in Difficult Times 15: Yuansi Chen Achieved a Major Breakthrough on Bourgain’s Slicing Problem and the Kannan, Lovász and Simonovits Conjecture
This post gives some background to a recent amazing breakthrough paper: An Almost Constant Lower Bound of the Isoperimetric Coefficient in the KLS Conjecture by Yuansi Chen. Congratulations Yuansi! The news Yuansi Chen gave an almost constant bounds for Bourgain’s … Continue reading
Posted in Combinatorics, Computer Science and Optimization, Convexity, Geometry
Tagged Yuansi Chen
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Open problem session of HUJICOMBSEM: Problem #2 Chaya Keller: The Krasnoselskii number
Marilyn Breen This is our second post on the open problem session of the HUJI combinatorics seminar. The video of the session is here. Today’s problem was presented by Chaya Keller. The Krasnoselskii number One of the bestknown applications … Continue reading
Posted in Combinatorics, Convexity
Tagged Chaya Keller, Marilyn Breen, Mark Krasnoselskii, Micha A. Perles
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To cheer you up in difficult times 4: Women In Theory present — I will survive
An amazing video (Update, May18 2020). I failed to explain what WIT is and this may have caused some misunderstanding. Here is a description from the Simons Institute site. “The Women in Theory (WIT) Workshop is intended for graduate and … Continue reading
Isabella Novik and Hailun Zheng: Neighborly centrally symmetric spheres exist in all dimensions!
A tweetlong summary: The cyclic polytope is wonderful and whenever we construct an analogous object we are happy. Examples: Neighborly cubic polytopes; The amplituhedron; and as of last week, the NovikZheng new construction of neighborly centrally symmetric spheres! At last: … Continue reading
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
Attila Por’s Universality Result for Tverberg Partitions
In this post I would like to tell you about three papers and three theorems. I am thankful to Moshe White and Imre Barany for helpful discussions. a) Universality of vector sequences and universality of Tverberg partitions, by Attila Por; Theorem … Continue reading