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 Some News from a Seminar in Cambridge
 Subspace Designs, Unit and Distinct Distances, and Piercing Standard Boxes.
 Greg Kuperberg @ Tel Aviv University
 Israel AGT Day, Reichman University, March 5, 2023
 Alef’s Corner: Democracy (Israel, 2023)
 Absolutely Sensational Morning News – Zander Kelley and Raghu Meka proved Behrendtype bounds for 3APs
 The Trifference Problem
 Greatest Hits 20152022, Part II
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Top Posts & Pages
 Some News from a Seminar in Cambridge
 Absolutely Sensational Morning News  Zander Kelley and Raghu Meka proved Behrendtype bounds for 3APs
 Greg Kuperberg @ Tel Aviv University
 Quantum Computers: A Brief Assessment of Progress in the Past Decade
 To cheer you up in difficult times 7: Bloom and Sisask just broke the logarithm barrier for Roth's theorem!
 'Gina Says'
 Answer: Lord Kelvin, The Age of the Earth, and the Age of the Sun
 R(5,5) ≤ 48
 The Argument Against Quantum Computers  A Very Short Introduction
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Monthly Archives: August 2008
A Diameter Problem (2)
2. The connection with Hirsch’s Conjecture The Hirsch Conjecture asserts that the diameter of the graph G(P) of a dpolytope P with n facets is at most nd. Not even a polynomial upper bound for the diameter in terms of d and … Continue reading
Posted in Combinatorics, Convex polytopes, Open problems
5 Comments
Two Very Early Problems, a Simple Solution, and a New Problem
As an undergraduate student whenever I studied some subject I tried to come up with problems. Many of these problems were artificial or silly and, of course, I forgot most of them. But a few still make sense. Here are … Continue reading
Posted in Open problems
9 Comments
Surprising Math
1. A pleasant surprise When I worked on the diameter problem for dpolytopes with n facets. I was aiming to prove an upper bound of the form but my proof only gave It was a pleasant surprise to note that . 2. … Continue reading
Posted in Uncategorized
4 Comments
Plans and Updates
Jerusalem and Budapest Monday, last week was the last day of lectures for the spring term here at the Hebrew U. One outcome of the long professors’ strike was a very fruitful year for research seminars. We ran them during … Continue reading
More Art: Tami’s Autoportrait
And in my office, there is a beautiful autoportrait by my sister Tamar Kalai. (Click for a deatiled picture.)
Our Department’s Quilt
Academic administation is a topic of great interest that desrves a special post. The highest post I served was as the department chair, and one thing I did was to acquire for the department a quilt by the artist Anna Maria … Continue reading