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 Second third of my ICM 2018 paper – Three Puzzles on Mathematics, Computation and Games. Corrections and comments welcome
 First third of my ICM2018 paper – Three Puzzles on Mathematics, Computation and Games. Corrections and comments welcome
 Preview: The solution by Keller and Lifshitz to several open problems in extremal combinatorics
 Basic Notions Seminar is Back! Helly Type Theorems and the Cascade Conjecture
 My Very First Book “Gina Says”, Now Published by “World Scientific”
 Itai Benjamini: Coarse Uniformization and Percolation & A Paper by Itai and me in Honor of Lucio Russo
 AfterDinner Speech for Alex Lubotzky
 Boaz Barak: The different forms of quantum computing skepticism
 Bálint Virág: Random matrices for Russ
Top Posts & Pages
 First third of my ICM2018 paper  Three Puzzles on Mathematics, Computation and Games. Corrections and comments welcome
 Answer: Lord Kelvin, The Age of the Earth, and the Age of the Sun
 Preview: The solution by Keller and Lifshitz to several open problems in extremal combinatorics
 Elchanan Mossel's Amazing Dice Paradox (your answers to TYI 30)
 Second third of my ICM 2018 paper  Three Puzzles on Mathematics, Computation and Games. Corrections and comments welcome
 Can Category Theory Serve as the Foundation of Mathematics?
 A Breakthrough by Maryna Viazovska Leading to the Long Awaited Solutions for the Densest Packing Problem in Dimensions 8 and 24
 TYI 30: Expected number of Dice throws
 Eran Nevo: gconjecture part 4, Generalizations and Special Cases
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Category Archives: Convex polytopes
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. Added later: Mazi and I at the same restaurant taken by Stanley. I just returned from … Continue reading
Posted in Combinatorics, Conferences, Convex polytopes
Tagged Alternating sign matrices, Convex polytopes, FPSAC, Japan
2 Comments
Satoshi Murai and Eran Nevo proved the Generalized Lower Bound Conjecture.
Satoshi Murai and Eran Nevo have just proved the 1971 generalized lower bound conjecture of McMullen and Walkup, in their paper On the generalized lower bound conjecture for polytopes and spheres . Let me tell you a little about it. … Continue reading
Updates, Boolean Functions Conference, and a Surprising Application to Polytope Theory
The Debate continues The debate between Aram Harrow and me on Godel Lost letter and P=NP (GLL) regarding quantum fault tolerance continues. The first post entitled Perpetual motions of the 21th century featured mainly my work, with a short response by Aram. … Continue reading
Projections to the TSP Polytope
Michael Ben Or told me about the following great paper Linear vs. Semidefinite Extended Formulations: Exponential Separation and Strong Lower Bounds by Samuel Fiorini, Serge Massar, Sebastian Pokutta, Hans Raj Tiwary and Ronald de Wolf. The paper solves an old conjecture … Continue reading
Polymath3 (PHC6): The Polynomial Hirsch Conjecture – A Topological Approach
This is a new polymath3 research thread. Our aim is to tackle the polynomial Hirsch conjecture which asserts that there is a polynomial upper bound for the diameter of graphs of dimensional polytopes with facets. Our research so far was … Continue reading
Posted in Convex polytopes, Geometry, Polymath3
Tagged Hirsch conjecture, Polymath3, Topological combinatorics
37 Comments
IPAM Remote Blogging: SantosWeibel 25Vertices Prismatoid and Prismatoids with large Width
Here is a web page by Christope Weibel on the improved counterexample. The IPAM webpage contains now slides of some of the lectures. Here are Santos’s slides. The last section contains some recent results on the “width of 5prismatoids” A prismatoid is a polytope … Continue reading
Remote Blogging: Efficiency of the Simplex Method: Quo vadis Hirsch conjecture?
Here are some links and posts related to some of the talks in IPAM’s workshop “Efficiency of the Simplex Method: Quo vadis Hirsch conjecture?” I will be happy to add links to pdf’s of the presentations and to relevant papers. Descriptions and … Continue reading
Subexponential Lower Bound for Randomized Pivot Rules!
Oliver Friedmann, Thomas Dueholm Hansen, and Uri Zwick have managed to prove subexponential lower bounds of the form for the following two basic randomized pivot rules for the simplex algorithm! This is the first result of its kind and deciding … Continue reading
Polymath3: Polynomial Hirsch Conjecture 4
So where are we? I guess we are trying all sorts of things, and perhaps we should try even more things. I find it very difficult to choose the more promising ideas, directions and comments as Tim Gowers and Terry Tao did so … Continue reading
Posted in Combinatorics, Convex polytopes, Open discussion, Open problems, Polymath3
Tagged Hirsch conjecture, Polymath3
74 Comments
Polymath3 : Polynomial Hirsch Conjecture 3
Here is the third research thread for the polynomial Hirsch conjecture. I hope that people will feel as comfortable as possible to offer ideas about the problem we discuss. Even more important, to think about the problem either in the directions suggested by … Continue reading
Posted in Combinatorics, Convex polytopes, Open discussion, Open problems, Polymath3
Tagged Polymath3
102 Comments