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- Some News from a Seminar in Cambridge
- Absolutely Sensational Morning News - Zander Kelley and Raghu Meka proved Behrend-type bounds for 3APs
- Greg Kuperberg @ Tel Aviv University
- Quantum Computers: A Brief Assessment of Progress in the Past Decade
- To cheer you up in difficult times 7: Bloom and Sisask just broke the logarithm barrier for Roth's theorem!
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Tag Archives: Lou Billera
Karim Adiprasito: The g-Conjecture for Vertex Decomposible Spheres
J Scott Provan (site) The following post was kindly contributed by Karim Adiprasito. (Here is the link to Karim’s paper.) Update: See Karim’s comment on the needed ideas for extend the proof to the general case. See also in the … Continue reading
Posted in Combinatorics, Convex polytopes, Geometry, Guest blogger
Tagged g-conjecture, J Scott Provan, Karim Adiprasito, Leonid Gurvits, Lou Billera
9 Comments
Beyond the g-conjecture – algebraic combinatorics of cellular spaces I
The g-conjecture for spheres is surely the one single conjecture I worked on more than on any other, and also here on the blog we had a sequence of posts about it by Eran Nevo (I,II,III,IV). Here is a great … Continue reading
Posted in Combinatorics, Convex polytopes, Geometry
Tagged Anders Bjorner, Bob MacPherson, Carl Lee, Ed Swartz, Eran Nevo, g-conjecture, Günter Ziegler, Isabella Novik, June Huh, Kalle Karu, Karim Adiprasito, Kazhdan-Lustig polynomials, Lou Billera, Marge Bayer, Peter McMullen, Richard Stanley, Ron Adin, Satoshi Murai, Tom Braden
14 Comments
(Eran Nevo) The g-Conjecture I
This post is authored by Eran Nevo. (It is the first in a series of five posts.) Peter McMullen The g-conjecture What are the possible face numbers of triangulations of spheres? There is only one zero-dimensional sphere and it consists … Continue reading
Posted in Combinatorics, Convex polytopes, Guest blogger, Open problems
Tagged Carl Lee, Eran Nevo, face rings, g-conjecture, Lou Billera, Peter McMullen, Polytopes, Richard Stanley
13 Comments
Euler’s Formula, Fibonacci, the Bayer-Billera Theorem, and Fine’s CD-index
Bill Gessley proving Euler’s formula (at UMKC) In the earlier post about Billerafest I mentioned the theorem of Bayer and Billera on flag numbers of polytopes. Let me say a little more about it. 1. Euler Euler’s theorem asserts that for … Continue reading
Posted in Combinatorics, Convex polytopes
Tagged Bayer-Billera's theorem, CD-index, Flag numbers, Jonathan Fine, Lou Billera, Marge Bayer
8 Comments
Billerafest
I am unable to attend the conference taking place now at Cornell, but I send my warmest greetings to Lou from Jerusalem. The titles and abstracts of the lectures can be found here. Let me tell you about two theorems by Lou. … Continue reading
Posted in Conferences, Convex polytopes
Tagged f-vectors, flag vectors, g-conjecture, Lou Billera
1 Comment