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- TYI 41: How many steps does it take for a simple random walk on the discrete cube to reach the uniform distribution?
- Gil’s Collegial Quantum Supremacy Skepticism FAQ
- Amazing! Keith Frankston, Jeff Kahn, Bhargav Narayanan, Jinyoung Park: Thresholds versus fractional expectation-thresholds
- Starting today: Kazhdan Sunday seminar: “Computation, quantumness, symplectic geometry, and information”
- The story of Poincaré and his friend the baker
- Gérard Cornuéjols’s baker’s eighteen 5000 dollars conjectures
- Noisy quantum circuits: how do we know that we have robust experimental outcomes at all? (And do we care?)
- Test Your Intuition 40: What Are We Celebrating on Sept, 28, 2019? (And answer to TYI39.)
- Quantum computers: amazing progress (Google & IBM), and extraordinary but probably false supremacy claims (Google).
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- Gil's Collegial Quantum Supremacy Skepticism FAQ
- TYI 41: How many steps does it take for a simple random walk on the discrete cube to reach the uniform distribution?
- Lior, Aryeh, and Michael
- TYI 30: Expected number of Dice throws
- Elchanan Mossel's Amazing Dice Paradox (your answers to TYI 30)
- Quantum computers: amazing progress (Google & IBM), and extraordinary but probably false supremacy claims (Google).
- Amazing: Hao Huang Proved the Sensitivity Conjecture!
- Jeff Kahn and Jinyoung Park: Maximal independent sets and a new isoperimetric inequality for the Hamming cube.
- Aubrey de Grey: The chromatic number of the plane is at least 5
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Tag Archives: Turan’s problem
Polymath 10 post 6: The Erdos-Rado sunflower conjecture, and the Turan (4,3) problem: homological approaches.
In earlier posts I proposed a homological approach to the Erdos-Rado sunflower conjecture. I will describe again this approach in the second part of this post. Of course, discussion of other avenues for the study of the conjecture are welcome. The purpose … Continue reading
The Combinatorics of Cocycles and Borsuk’s Problem.
Cocycles Definition: A -cocycle is a collection of -subsets such that every -set contains an even number of sets in the collection. Alternative definition: Start with a collection of -sets and consider all -sets that contain an odd number of members … Continue reading
A Small Debt Regarding Turan’s Problem
Turan’s problem asks for the minimum number of triangles on n vertices so that every 4 vertices span a triangle. (Or equivalently, for the maximum number of triangles on n vertices without a “tetrahedron”, namely without having four triangles on … Continue reading
Local Events, Turan’s Problem and Limits of Graphs and Hypergraphs
I will write a little about how hectic things are now here at HU, and make two (somewhat related) follow-ups on previous posts: Tell you about Turan’s problem, and about Balázs Szegedi’s lecture from Marburg dealing with limits of graphs and hypergraphs. Local Events … Continue reading
Posted in Combinatorics, Open problems
Tagged Extremal combinatorics, Graph limits, Quasirandomness, Turan's problem
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Extremal Combinatorics I: Extremal Problems on Set Systems
The “basic notion seminar” is an initiative of David Kazhdan who joined HU math department around 2000. People give series of lectures about basic mathematics (or not so basic at times). Usually, speakers do not talk about their own research and not even … Continue reading