Reputation
10,507
Next privilege 15,000 Rep.
Protect questions
Badges
16 136 222
Impact
~1.4m people reached

Jan
31
awarded  Good Question
Jan
30
revised The shortest path in first passage percolation
added 121 characters in body; edited tags
Jan
28
awarded  Nice Answer
Jan
27
awarded  Popular Question
Jan
26
revised What is an integrable system
edited tags
Jan
26
comment Experimental Mathematics
A quotient of a polytope P corresponds to an interval in the face lattice: all the faces that contain a face G and are contained in a face H. The set of these faces are the set of faces of a polytope Q of dmension dim G - dim H - 1. Intervals of the form [emptyset, F] simply correspond to the faces of F. Polyope duality allow you to think easily about intervals of the form [F,P].
Jan
26
awarded  Popular Question
Jan
26
answered Experimental Mathematics
Jan
26
comment Weighted Regular Graphs
when you consider a vertex v youtake sum w(u) for all edge {v,u} so the weight of v does not matter except when you have a loop (so when u=v)
Jan
26
comment Expected determinant of a random NxN matrix.
There is another simple proof based on Cauchy Binet theorem. Turan published (in Chinese) a formula for the sum of the 4th power. (I think there are simpler proof but I dont know a reference). I am not aware of a formula for higher powers.
Jan
26
revised Weighted Regular Graphs
edited tags
Jan
26
answered Experimental Mathematics
Jan
26
asked Weighted Regular Graphs
Jan
25
comment Taking lecture notes in lectures
Anton, does live texing requires the ability for blind typing?
Jan
23
comment The shortest path in first passage percolation
I am not sure if a bounty is an effective tool for an open problem that might be hard. Maybe it will lead to having another round of thoughts about it, which I feel, in good conscious, that the problem deserves
Jan
23
awarded  Nice Question
Jan
22
comment Switching Research Fields
Dear Alex, Each of the areas you describe requires a substantial amount of investement, and trying to do research in parallel in several areas may not be a good idea. It can be a joy to widen the horizons, but when it comes to research it is also important to learn to stay focused, and to set realistic aims.
Jan
22
comment Taking lecture notes in lectures
I still think that the very best lectures are good lectures.
Jan
22
comment Taking lecture notes in lectures
Done! This question was promised here: gilkalai.wordpress.com/2008/07/15/arrows-economics-1
Jan
22
asked Taking lecture notes in lectures