Author Archives: Gil Kalai

The Privacy Paradox of Rann Smorodinsky

   The following paradox was raised by Rann Smorodinsky: Rann Smorodinsky’s Privacy Paradox Suppose that you have the following one-time scenario. You want to buy a sandwich where the options are a roast beef sandwich or an avocado sandwich. Choosing … Continue reading

Posted in Games, Philosophy, Rationality | Tagged , , | 17 Comments

Happy Birthday Ron Aharoni!

Ron Aharoni, one of Israel’s and the world’s leading combinatorialists celebrated his birthday last month. This is a wonderful opportunity to tell you about a few of the things that Ron did mainly around matching theory. Menger’s theorem for infinite … Continue reading

Posted in Combinatorics | Tagged , , , , | Leave a comment

A Few Mathematical Snapshots from India (ICM2010)

Can you find Assaf in this picture? (Picture: Guy Kindler.) In my post about ICM 2010 and India I hardly mentioned any mathematics. So here are a couple of mathematical snapshots from India. Not so much from the lectures themselves but … Continue reading

Posted in Conferences, Open problems | Tagged , , , , | 1 Comment

Karim Adiprasito: Flag simplicial complexes and the non-revisiting path conjecture

This post is authored by Karim Adiprasito The past months have seen some exciting progress on diameter bounds for polytopes and polytopal complexes, both in the negative and in the positive direction.  Jesus de Loera and Steve Klee described simplicial polytopes which are not  … Continue reading

Posted in Convex polytopes, Guest blogger | Tagged , , , | Leave a comment

The Quantum Debate is Over! (and other Updates)

Quid est noster computationis mundus? Nine months after is started, (much longer than expected,) and after eight posts on GLL, (much more than planned,)  and almost a thousand comments of overall good quality,   from quite a few participants, my … Continue reading

Posted in Combinatorics, Computer Science and Optimization, Controversies and debates, Updates | Tagged , , | 3 Comments

Looking Again at Erdős’ Discrepancy Problem

Over Gowers’s blog Tim and I will make an attempt to revisit polymath5. Last Autumn I prepared three posts on the problems and we decided to launch them now. The first post is here. Here is a related MathOverflow question. … Continue reading

Posted in Combinatorics, Mathematics over the Internet, Open problems | 2 Comments

Tokyo, Kyoto, and Nagoya

Near Nagoya: Firework festival; Kyoto: with Gunter Ziegler; with Takayuki Hibi, Hibi, Marge Bayer, Curtis Green and Richard Stanly; Tokyo: Peter Frankl; crowded crossing I just returned from a trip to Japan to the FPSAC 2012 at Nagoya and a … Continue reading

Posted in Combinatorics, Conferences, Convex polytopes | Tagged , , , | 2 Comments

A Weak Form of Borsuk Conjecture

Problem: Let P be a polytope in with n facets. Is it always true that P can be covered by n sets of smaller diameter?   I also asked this question over mathoverflow, with some background and motivation.

Posted in Convexity, Open problems | Tagged | Leave a comment

Some Updates

Jeff Kahn was in town: so we worked together also with Ehud Friedgut and Roy Meshulam (and others) quite intensively. Very nice! Stay tuned for a report! Polynomial Hirsch conjecture (polymath3): While the conjecture remains wide open there are some … Continue reading

Posted in Updates | 3 Comments

Eyal Sulganik: Towards a Theory of “Mathematical Accounting”

The following post was kindly contributed by Eyal Sulganik  from IDC (Interdiciplinary Center)  Herzliya. Eyal was motivated by our poll on certainty “beyond a reasonable doubt,” which is related to several issues in accounting. Mathematicians, I believe, are always looking … Continue reading

Posted in Economics, Games, Guest blogger, Law | Tagged , | 3 Comments