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 To cheer you up in difficult times 21: Giles Gardam lecture and new result on Kaplansky’s conjectures
 Nostalgia corner: John Riordan’s referee report of my first paper
 At the Movies III: Picture a Scientist
 At the Movies II: Kobi Mizrahi’s short movie White Eye makes it to the Oscar’s short list.
 And the Oscar goes to: Meir Feder, Zvi Reznic, Guy Dorman, and Ron Yogev
 Thomas Vidick: What it is that we do
 To cheer you up in difficult times 20: Ben Green presents superpolynomial lower bounds for offdiagonal van der Waerden numbers W(3,k)
 To cheer you up in difficult times 19: Nati Linial and Adi Shraibman construct larger cornerfree sets from better numbersontheforehead protocols
 Possible future Polymath projects (2009, 2021)
Top Posts & Pages
 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
 To cheer you up in difficult times 21: Giles Gardam lecture and new result on Kaplansky's conjectures
 TYI 30: Expected number of Dice throws
 8866128975287528³+(8778405442862239)³+(2736111468807040)³
 The Argument Against Quantum Computers  A Very Short Introduction
 Answer: Lord Kelvin, The Age of the Earth, and the Age of the Sun
 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.
 Possible future Polymath projects (2009, 2021)
 Photonic Huge Quantum Advantage ???
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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