Monthly Archives: September 2019

Test Your Intuition 40: What Are We Celebrating on Sept, 28, 2019? (And answer to TYI39.)

Posted on September 28, 2019 by Gil Kalai

Update: We are celebrating 10 years anniversary to Mathoverflow Domotorp got the answer right. congratulations, Domotorp! To all our readers: Shana Tova Umetuka –  שנה טובה ומתוקה – Happy and sweet (Jewish) new year.

Posted in Test your intuition, What is Mathematics | Tagged , | 6 Comments

Quantum computers: amazing progress (Google & IBM), and extraordinary but probably false supremacy claims (Google).

Posted on September 23, 2019 by Gil Kalai

A 2017 cartoon from this post. After the embargo update (Oct 25): Now that I have some answers from the people involved let me make a quick update: 1) I still find the paper  unconvincing, specifically, the verifiable experiments (namely experiments … Continue reading →

Posted in Combinatorics, Computer Science and Optimization, Quantum, Updates | Tagged | 68 Comments

Jeff Kahn and Jinyoung Park: Maximal independent sets and a new isoperimetric inequality for the Hamming cube.

Posted on September 22, 2019 by Gil Kalai

Three isoperimetric papers by Michel Talagrand (see the end of the post) Discrete isoperimetric relations are of great interest on their own and today I want to tell you about a new  isoperimetric inequality by Jeff Kahn and Jinyoung Park … Continue reading →

Posted in Combinatorics | Tagged , , | 4 Comments

Alef’s corner: Bicycles and the Art of Planar Random Maps

Posted on September 17, 2019 by Gil Kalai

The artist behind Alef’s corner has a few mathematical designs and here are two new ones. (See Alef’s  website offering over 100 T-shirt designs.)   which was used for the official T-shirt for Jean-François Le Gall’s birthday conference. See also … Continue reading →

Posted in Art, Combinatorics, Geometry, Probability | Tagged | Leave a comment

Paul Balister, Béla Bollobás, Robert Morris, Julian Sahasrabudhe, and Marius Tiba: Flat polynomials exist!

Posted on September 9, 2019 by Gil Kalai

Béla Bollobás and Paul Erdős at the University of Cambridge in 1990. Credit George Csicsery (from the 1993 film “N is a Number”) (source) (I thank Gady Kozma for telling me about the result.) An old problem from analysis with a … Continue reading →

Posted in Analysis, Combinatorics | Tagged , , , , , | 1 Comment

Computer Science and its Impact on our Future

Posted on September 4, 2019 by Gil Kalai

A couple of weeks ago I told you about Avi Wigderson’s vision on the connections between the theory of computing and other areas of mathematics on the one hand and between computer science and other areas of science, technology and … Continue reading →

Posted in Academics, Computer Science and Optimization, Quantum, Updates | Tagged | 1 Comment

Richard Ehrenborg’s problem on spanning trees in bipartite graphs

Posted on September 1, 2019 by Gil Kalai

Richard Ehrenborg with a polyhedron In the Problem session last Thursday in Oberwolfach, Steve Klee presented a beautiful problem of Richard Ehrenborg regarding the number of spanning trees in bipartite graphs. Let be a bipartite graph with vertices on one … Continue reading →

Posted in Combinatorics, Open problems | Tagged , | 4 Comments