Monthly Archives: December 2009

Randomness in Nature

Posted on December 27, 2009 by

Here is an excellent question asked by Liza on “Mathoverflow“. What is the explanation of the apparent randomness of high-level phenomena in nature? For example the distribution of females vs. males in a population (I am referring to randomness in terms … Continue reading →

Posted in Probability | Tagged , , , , | 22 Comments

Midrasha News

Posted on December 22, 2009 by

Our Midrasha is going very very well. There are many great talks, mostly very clear and helpful. Various different directions which interlace very nicely. Some moving new mathematical breakthroughs; very few fresh from the oven. Tomorrow is the last day. Update: I will try … Continue reading →

Posted in Conferences, Probability | Tagged | 4 Comments

Joe Malkevitch: Why Planar Graphs are so Exceptional

Posted on December 21, 2009 by

  Not only do interesting questions arise by considering the special class of planar graphs but additional special issues arise when one considers a specific plane drawing of a planar graph. This is because when a graph is drawn in … Continue reading →

Posted in Combinatorics, Guest blogger | 6 Comments

When Noise Accumulates

Posted on December 9, 2009 by

I wrote a short paper entitled “when noise accumulates” that contains the main conceptual points (described rather formally) of my work regarding noisy quantum computers.  Here is the paper. (Update: Here is a new version, Dec 2010.) The new exciting innovation in computer … Continue reading →

Posted in Computer Science and Optimization, Physics | Tagged , , , | 9 Comments

Plans for polymath3

Posted on December 8, 2009 by

Polymath3 is planned to study the polynomial Hirsch conjecture. In order not to conflict with Tim Gowers’s next polymath project which I suppose will start around January, I propose that we will start polymath3 in mid April 2010. I plan to write a … Continue reading →

Posted in Convex polytopes, Polymath3 | Tagged , | 4 Comments

Four Derandomization Problems

Posted on December 6, 2009 by

Polymath4 is devoted to a question about derandomization: To find a deterministic polynomial time algorithm for finding a k-digit prime.  So I (belatedly) devote this post to derandomization and, in particular, the following four problems. 1) Find a deterministic algorithm for primality 2) Find … Continue reading →

Posted in Computer Science and Optimization, Probability | Tagged , , | 4 Comments

Why are Planar Graphs so Exceptional

Posted on December 3, 2009 by

Harrison Brown asked the problem “Why are planar graphs  so exceptional” over mathoverflow, and I was happy to read it since it is a problem I have often thought about over the years, as I am sure have  many combinatorialsists and graph … Continue reading →

Posted in Combinatorics, Convex polytopes | 2 Comments