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- Stefan Steinerberger: The Ulam Sequence
- TYI 26: Attaining the Maximum
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- A Breakthrough by Maryna Viazovska Leading to the Long Awaited Solutions for the Densest Packing Problem in Dimensions 8 and 24
- Answer: Lord Kelvin, The Age of the Earth, and the Age of the Sun
- The Quantum Computer Puzzle @ Notices of the AMS
- Three Conferences: Joel Spencer, April 29-30, Courant; Joel Hass May 20-22, Berkeley, Jean Bourgain May 21-24, IAS, Princeton
- Polymath10: The Erdos Rado Delta System Conjecture
- János Pach: Guth and Katz's Solution of Erdős's Distinct Distances Problem
- Seven Problems Around Tverberg's Theorem
- Believing that the Earth is Round When it Matters
- Stefan Steinerberger: The Ulam Sequence

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# Monthly Archives: December 2009

## Randomness in Nature

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 foundation of probability, Math Overflow, Philosophy, Physics, Randomness
22 Comments

## Midrasha News

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

## Joe Malkevitch: Why Planar Graphs are so Exceptional

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

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

## Plans for polymath3

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

## Four Derandomization Problems

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 derandomization, polymath4, Randomness
7 Comments

## Why are Planar Graphs so Exceptional

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