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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
 Possible future Polymath projects (2009, 2021)
 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.
 Photonic Huge Quantum Advantage ???
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Monthly Archives: July 2008
A Diamater Problem for Families of Sets.
Let me draw your attention to the following problem: Consider a family of subsets of size d of the set N={1,2,…,n}. Associate to a graph as follows: The vertices of are simply the sets in . Two vertices and are adjacent … Continue reading
Posted in Combinatorics, Convex polytopes, Open problems
10 Comments
Extremal Combinatorics II: Some Geometry and Number Theory
Extremal problems in additive number theory Our first lecture dealt with extremal problems for families of sets. In this lecture we will consider extremal problems for sets of real numbers, and for geometric configurations in planar Euclidean geometry. Problem I: Given a set A of … Continue reading
Arrow’s Economics 1
The annual Summer School in Economics at HU was directed until last year by Kenneth Arrow, along with Eyal Winter. Arrow decided this year to step down as a director and Eric Maskin is replacing him. The 2008 Summer School was … Continue reading
Pushing Behrend Around
Erdos and Turan asked in 1936: What is the largest subset of {1,2,…,n} without a 3term arithmetic progression? In 1946 Behrend found an example with Now, sixty years later, Michael Elkin pushed the the factor from the denominator to the enumerator, … Continue reading
Posted in Combinatorics, Updates
Tagged Arithmetic progressions, Roth's theorem, Szemeredi's theorem
14 Comments
From Helly to Cayley IV: Probability
I decided to split long part III into two parts. This (truly) last part of this series deals with probabilistic problems and with combinatorial questions regarding higher Laplacians. 21. Higher Laplacians and their meanings Our high dimensional extension to Cayley’s … Continue reading
Posted in Combinatorics, Probability
8 Comments
A New RectorElect at the Hebrew University of Jerusalem
Professor Sarah Stroumsa On Wednesday, the Senate of the Hebrew University of Jerusalem elected Professor Sarah Stroumsa (homepage) as the next Rector (provost) of the Hebrew University. For the first time since its establishment, the Hebrew University has elected a woman to its highest post … Continue reading
Helly, Cayley, Hypertrees, and Weighted Enumeration III
This is the third and last part of the journey from a Helly type conjecture of Katchalski and Perles to a Cayley’s type formula for “hypertrees”. (On second thought I decided to divide it into two devoting the second to probabilistic questions.) … Continue reading
Posted in Combinatorics, Convexity, Open problems, Probability
7 Comments