Recent Comments

Recent Posts
 Test Your Intuition about the AlonTarsi Conjecture
 Thilo Weinert: Transfinite Ramsey Numbers
 Timothy Chow Launched Polymath12 on Rota Basis Conjecture and Other News
 Proof By Lice!
 The seventeen camels riddle, and Noga Alon’s camel proof and algorithms
 Edmund Landau and the Early Days of the Hebrew University of Jerusalem
 Boolean Functions: Influence, Threshold, and Noise
 Laci Babai Visits Israel!
 Polymath10 conclusion
Top Posts & Pages
 Answer: Lord Kelvin, The Age of the Earth, and the Age of the Sun
 A Breakthrough by Maryna Viazovska Leading to the Long Awaited Solutions for the Densest Packing Problem in Dimensions 8 and 24
 Extremal Combinatorics IV: Shifting
 The seventeen camels riddle, and Noga Alon's camel proof and algorithms
 Randomness in Nature
 In how many ways you can chose a committee of three students from a class of ten students?
 Randomness in Nature II
 The Erdős Szekeres polygon problem  Solved asymptotically by Andrew Suk.
 Thilo Weinert: Transfinite Ramsey Numbers
RSS
Search Results for: erdos
When Do a Few Colors Suffice?
When can we properly color the vertices of a graph with a few colors? This is a notoriously difficult problem. Things get a little better if we consider simultaneously a graph together with all its induced subgraphs. Recall that an … Continue reading
School Starts at HUJI
We are now starting the third week of the academic year at HUJI. As usual, things are very hectic, a lot of activities in the mathematics department, in our sister CS department, around in the campus, and in our combinatorics … Continue reading
Posted in Updates
Leave a comment
Happy Birthday Ervin, János, Péter, and Zoli!
The four princes in summit 200, ten years ago. (Left to right) Ervin Győri, Zoltán Füredi, Péter Frankl and János Pach In 2014, Péter Frankl, Zoltán Füredi, Ervin Győri and János Pach are turning 60 and summit 240 is a conference … Continue reading
Posted in Conferences, Happy birthday
3 Comments
Happy Birthday Richard Stanley!
This week we are celebrating in Cambridge MA , and elsewhere in the world, Richard Stanley’s birthday. For the last forty years, Richard has been one of the very few leading mathematicians in the area of combinatorics, and he found deep, profound, and … Continue reading
Levon Khachatrian’s Memorial Conference in Yerevan
Workshop announcement The National Academy of Sciences of Armenia together American University of Armenia are organizing a memorial workshop on extremal combinatorics, cryptography and coding theory dedicated to the 60th anniversary of the mathematician Levon Khachatrian. Professor Khachatrian started his … Continue reading
Analysis of Boolean Functions week 5 and 6
Lecture 7 First passage percolation 1) Models of percolation. We talked about percolation introduced by Broadbent and Hammersley in 1957. The basic model is a model of random subgraphs of a grid in ndimensional space. (Other graphs were considered later as … Continue reading
Posted in Combinatorics, Computer Science and Optimization, Probability, Teaching
Tagged Arrow's theorem, Percolation
Leave a comment
Analysis of Boolean Functions – Week 3
Lecture 4 In the third week we moved directly to the course’s “punchline” – the use of FourierWalsh expansion of Boolean functions and the use of Hypercontractivity. Before that we started with a very nice discrete isoperimetric question on a … Continue reading
Around Borsuk’s Conjecture 3: How to Save Borsuk’s conjecture
Borsuk asked in 1933 if every bounded set K of diameter 1 in can be covered by d+1 sets of smaller diameter. A positive answer was referred to as the “Borsuk Conjecture,” and it was disproved by Jeff Kahn and me in 1993. … Continue reading
Analysis of Boolean Functions – week 1
Home page of the course. In the first lecture I defined the discrete ndimensional cube and Boolean functions. Then I moved to discuss five problems in extremal combinatorics dealing with intersecting families of sets. 1) The largest possible intersecting family … Continue reading
Open Collaborative Mathematics over the Internet – Three Examples
After much hesitation, I decided to share with you the videos of my lecture: Open collaborative mathematics over the internet – three examples, that I gave last January in Doron Zeilberger’s seminar at Rutgers on experimental mathematics. Parts of the 47minutes … Continue reading