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 Game Theory  online Course at IDC, Herzliya
 TYI44: "What Then, To Raise an Old Question, is Mathematics?"
 Kelman, Kindler, Lifshitz, Minzer, and Safra: Towards the EntropyInfluence Conjecture
 TYI 30: Expected number of Dice throws
 To cheer you up in complicated times  A book proof by Rom Pinchasi and Alexandr Polyanskii for a 1978 Conjecture by Erdős and Purdy!
 When Do a Few Colors Suffice?
 A sensation in the morning news  Yaroslav Shitov: Counterexamples to Hedetniemi's conjecture.
 The seventeen camels riddle, and Noga Alon's camel proof and algorithms
 Quantum computers: amazing progress (Google & IBM), and extraordinary but probably false supremacy claims (Google).
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Tag Archives: gconjecture
Karim Adiprasito: The gConjecture 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 gconjecture, J Scott Provan, Karim Adiprasito, Leonid Gurvits, Lou Billera
9 Comments
Amazing: Karim Adiprasito proved the gconjecture for spheres!
Karim in his youth with a fan Congratulations, Karim! Update: Here is the link to the paper From the arXive, Dec 26, 2018. (Link will be added tomorrow.) COMBINATORIAL LEFSCHETZ THEOREMS BEYOND POSITIVITY by Karim Adiprasito Abstract: Consider a simplicial complex … Continue reading
Beyond the gconjecture – algebraic combinatorics of cellular spaces I
The gconjecture 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, gconjecture, Günter Ziegler, Isabella Novik, June Huh, Kalle Karu, Karim Adiprasito, KazhdanLustig polynomials, Lou Billera, Marge Bayer, Peter McMullen, Richard Stanley, Ron Adin, Satoshi Murai, Tom Braden
10 Comments
Eran Nevo: gconjecture part 4, Generalizations and Special Cases
This is the fourth in a series of posts by Eran Nevo on the gconjecture. Eran’s first post was devoted to the combinatorics of the gconjecture and was followed by a further post by me on the origin of the gconjecture. Eran’s second post was about … Continue reading
Posted in Combinatorics, Convex polytopes, Guest blogger, Open problems
Tagged Eran Nevo, gconjecture
2 Comments
Convex Polytopes: Seperation, Expansion, Chordality, and Approximations of Smooth Bodies
I am happy to report on two beautiful results on convex polytopes. One disproves an old conjecture of mine and one proves an old conjecture of mine. Loiskekoski and Ziegler: Simple polytopes without small separators. Does LiptonTarjan’s theorem extends to high … Continue reading
(Eran Nevo) The gConjecture III: Algebraic Shifting
This is the third in a series of posts by Eran Nevo on the gconjecture. Eran’s first post was devoted to the combinatorics of the gconjecture and was followed by a further post by me on the origin of the gconjecture. … Continue reading
Posted in Combinatorics, Convex polytopes, Guest blogger, Open problems
Tagged algebraic shifting, Eran Nevo, gconjecture, Karanbir Sarkaria, Shifting
5 Comments
(Eran Nevo) The gConjecture II: The Commutative Algebra Connection
Richard Stanley This post is authored by Eran Nevo. (It is the second in a series of five posts.) The gconjecture: the commutative algebra connection Let be a triangulation of a dimensional sphere. Stanley’s idea was to associate with a ring … Continue reading
How the gConjecture Came About
Update: Slides from a great 2014 lecture on the gconjecture by Lou Billera in the conference celebrating Richard Stanley’s 70th birthday. This post complements Eran Nevo’s first post on the conjecture 1) Euler’s theorem Euler Euler’s famous formula for the … Continue reading
(Eran Nevo) The gConjecture I
This post is authored by Eran Nevo. (It is the first in a series of five posts.) Peter McMullen The gconjecture What are the possible face numbers of triangulations of spheres? There is only one zerodimensional sphere and it consists … Continue reading
Posted in Combinatorics, Convex polytopes, Guest blogger, Open problems
Tagged Carl Lee, Eran Nevo, face rings, gconjecture, Lou Billera, Peter McMullen, Polytopes, Richard Stanley
12 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 fvectors, flag vectors, gconjecture, Lou Billera
1 Comment