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 Combinatorics and More – Greatest Hits
 Ilan and me
 The Simplex, the Cyclic polytope, the Positroidron, the Amplituhedron, and Beyond
 From Oberwolfach: The Topological Tverberg Conjecture is False
 Midrasha Mathematicae #18: In And Around Combinatorics
 Quantum computing: achievable reality or unrealistic dream
 A Historical Picture Taken by Nimrod Megiddo
 Scott Triumphs* at the Shtetl
 Amy Triumphs* at the Shtetl
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 Combinatorics and More  Greatest Hits
 Academic Degrees and Sex
 The KadisonSinger Conjecture has beed Proved by Adam Marcus, Dan Spielman, and Nikhil Srivastava
 Combinatorics, Mathematics, Academics, Polemics, ...
 The AC0 Prime Number Conjecture
 Ziegler´s Lecture on the Associahedron
 From Oberwolfach: The Topological Tverberg Conjecture is False
 The Simplex, the Cyclic polytope, the Positroidron, the Amplituhedron, and Beyond
 Five Open Problems Regarding Convex Polytopes
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Author Archives: Gil Kalai
Combinatorics and More – Greatest Hits
Combinatorics and More’s Greatest Hits First Month Combinatorics, Mathematics, Academics, Polemics, … Helly’s Theorem, “Hypertrees”, and Strange Enumeration I (There were 3 follow up posts:) Extremal Combinatorics I: Extremal Problems on Set Systems (There were 4 follow up posts II ; III; IV; VI) Drachmas Rationality, Economics and … Continue reading
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The Simplex, the Cyclic polytope, the Positroidron, the Amplituhedron, and Beyond
A quick schematic roadmap to these new geometric objects. The positroidron can be seen as a cellular structure on the nonnegative Grassmanian – the part of the real Grassmanian G(m,n) which corresponds to m by n matrices with all m by … Continue reading
From Oberwolfach: The Topological Tverberg Conjecture is False
The topological Tverberg conjecture (discussed in this post), a holy grail of topological combinatorics, was refuted! The threepage paper “Counterexamples to the topological Tverberg conjecture” by Florian Frick gives a brilliant proof that the conjecture is false. The proof is … Continue reading
Posted in Combinatorics, Conferences, Convexity, Updates
Tagged Florian Frick, Issac Mabillard, Uli Wagner
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Midrasha Mathematicae #18: In And Around Combinatorics
Tahl Nowik Update 3 (January 30): The midrasha ended today. Update 2 (January 28): additional videos are linked; Update 1 (January 23): Today we end the first week of the school. David Streurer and Peter Keevash completed … Continue reading
Posted in Combinatorics, Conferences, Updates
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A Historical Picture Taken by Nimrod Megiddo
Last week I took a bus from Tel Aviv to Jerusalem and I saw (from behind) a person that I immediately recognized. It was Nimrod Megiddo, from IBM Almaden, one of the very first to relate game theory with complexity … Continue reading
Scott Triumphs* at the Shtetl
Scott Aaronson wrote a new post on the Shtetl Optimized** reflecting on the previous thread (that I referred to in my post on Amy’s triumph), and on reactions to this thread. The highlight is a list of nine of Scott’s … Continue reading
Amy Triumphs* at the Shtetl
It was not until the 144th comment by a participants named Amy on Scott’s Aaronson recent Shtetloptimized** post devoted to a certain case of sexual harassment at M. I. T. that the discussion turned into something quite special. Amy’s great … Continue reading
Posted in Controversies and debates, Women in science
Tagged Amy, feminism, Shtetloptimized
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@HUJI
Ilya Rips and me during Ilyafest last week (picture Itai Benjamini) Ilya Rips Birthday Conference Last week we had here a celebration for Ilya Rips’ birthday. Ilya is an extraordinary mathematician with immense influence on algebra and topology. There were … Continue reading