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 A Nice Example Related to the Frankl Conjecture
 Amazing: Justin Gilmer gave a constant lower bound for the unionclosed sets conjecture
 Barnabás Janzer: Rotation inside convex Kakeya sets
 Inaugural address at the Hungarian Academy of Science: The Quantum Computer – A Miracle or Mirage
 Remarkable: “Limitations of Linear CrossEntropy as a Measure for Quantum Advantage,” by Xun Gao, Marcin Kalinowski, ChiNing Chou, Mikhail D. Lukin, Boaz Barak, and Soonwon Choi
 James Davies: Every finite colouring of the plane contains a monochromatic pair of points at an odd distance from each other.
 Bo’az Klartag and Joseph Lehec: The Slice Conjecture Up to Polylogarithmic Factor!
 Alef’s Corner: “It won’t work, sorry”
 Test Your intuition 51
Top Posts & Pages
 Amazing: Justin Gilmer gave a constant lower bound for the unionclosed sets conjecture
 A Nice Example Related to the Frankl Conjecture
 The Möbius Undershirt
 R(5,5) ≤ 48
 Amazing: Jinyoung Park and Huy Tuan Pham settled the expectation threshold conjecture!
 Remarkable: "Limitations of Linear CrossEntropy as a Measure for Quantum Advantage," by Xun Gao, Marcin Kalinowski, ChiNing Chou, Mikhail D. Lukin, Boaz Barak, and Soonwon Choi
 Gödel, Hilbert and Brouwer
 Why are Planar Graphs so Exceptional
 To cheer you up in difficult times 11: Immortal Songs by Sabine Hossenfelder and by Tom Lehrer
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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