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 High Dimensional Combinatorics at the IIAS – Program Starts this Week; My course on Hellytype theorems; A workshop in Sde Boker
 Stan Wagon, TYI 23: Ladies and Gentlemen: The Answer
 Ladies and Gentlemen, Stan Wagon: TYI 32 – A Cake Problem.
 If Quantum Computers are not Possible Why are Classical Computers Possible?
 Sergiu Hart: TwoVote or not to Vote
 A toast to Alistair: Two Minutes on Two Great Professional Surprises
 TYI 31 – Rados Radoicic’s Rope Problem
 Eran Nevo: gconjecture part 4, Generalizations and Special Cases
 The World of Michael Burt: When Architecture, Mathematics, and Art meet.
Top Posts & Pages
 Stan Wagon, TYI 23: Ladies and Gentlemen: The Answer
 High Dimensional Combinatorics at the IIAS  Program Starts this Week; My course on Hellytype theorems; A workshop in Sde Boker
 Ladies and Gentlemen, Stan Wagon: TYI 32  A Cake Problem.
 TYI 30: Expected number of Dice throws
 If Quantum Computers are not Possible Why are Classical Computers Possible?
 Elchanan Mossel's Amazing Dice Paradox (your answers to TYI 30)
 Answer: Lord Kelvin, The Age of the Earth, and the Age of the Sun
 The Race to Quantum Technologies and Quantum Computers (Useful Links)
 Why Quantum Computers Cannot Work: The Movie!
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Author Archives: Gil Kalai
Some Mathematical Puzzles that I encountered during my career
Recently, I gave some lectures based on a generalaudience personal tour across four (plus one) mathematical puzzles that I encountered during my career. Here is a paper based on these lectures which is meant for a very wide audience (in … Continue reading
Friendship and Sesame, Maryam and Marina, Israel and Iran
Happy new (Jewish) year everybody. Amazing scientific partnership between Jordan, Cyprus, Egypt, Iran, Israel, Pakistan, the Palestinian Authority, and Turkey SESAME (Synchrotronlight for Experimental Science and Applications in the Middle East) is a “thirdgeneration” synchrotron light source that was officially opened in Allan (Jordan) on 16 May 2017. … Continue reading
Posted in Obituary, Updates, Women in science
Tagged Eliezer Rabinovici, IsraelIran relationship, Marina Ratner, Maryam Mirzakhani, Sesame
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Elchanan Mossel’s Amazing Dice Paradox (your answers to TYI 30)
TYI 30 asked Elchanan Mossel’s Amazing Dice Paradox (that I heard from Yuval Peres yesterday) You throw a die until you get 6. What is the expected number of throws (including the throw giving 6) conditioned on the event that all throws … Continue reading
Posted in Combinatorics, Probability, Test your intuition
Tagged condition probability, Elchanan Mossel
62 Comments
TYI 30: Expected number of Dice throws
Test your intuition: You throw a dice until you get 6. What is the expected number of throws (including the throw giving 6) conditioned on the event that all throws gave even numbers. followup post
Test your intuition 29: Diameter of various random trees
Both trees in general and random trees in particular are wonderful objects. And there is nothing more appropriate to celebrate Russ Lyons great birthday conference “Elegance in Probability” (taking place now in Tel Aviv) than to test your intuition, dear … Continue reading
Posted in Combinatorics, Probability, Test your intuition
Tagged Russ Lyons, Test your intuition
18 Comments
Micha Perles’ Geometric Proof of the ErdosSos Conjecture for Caterpillars
A geometric graph is a set of points in the plane (vertices) and a set of line segments between certain pairs of points (edges). A geometric graph is simple if the intersection of two edges is empty or a vertex … Continue reading
Touching Simplices and Polytopes: Perles’ argument
Joseph Zaks (1984), picture taken by Ludwig Danzer (OberWolfach photo collection) The story I am going to tell here was told in several places, but it might be new to some readers and I will mention my own angle, … Continue reading
Posted in Combinatorics, Convex polytopes, Geometry, Open problems
Tagged Joseph Zaks, Micha A. Perles
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Where were we?
I was slow blogging, and catching up won’t be so easy. Of course, this brings me back to the question of what I should blog about. Ideally, I should tell you about mathematical things I heard about. The problem is … Continue reading
Call for nominations for the Ostrowski Prize 2017
Call for nominations for the Ostrowski Prize 2017 The aim of the Ostrowski Foundation is to promote the mathematical sciences. Every second year it provides a prize for recent outstanding achievements in pure mathematics and in the foundations of … Continue reading