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Recent Posts
- 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).
Top Posts & Pages
- 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?
- TYI 30: Expected number of Dice throws
- Lior, Aryeh, and Michael
- 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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Monthly Archives: August 2017
Micha Perles’ Geometric Proof of the Erdos-Sos Conjecture for Caterpillars
A geometric graph is a set of points in the plane (vertices) and a set of line segments between certain pairs of points (edges). A geometric graph is simple if the intersection of two edges is empty or a vertex … Continue reading
Touching Simplices and Polytopes: Perles’ argument
Joseph Zaks (1984), picture taken by Ludwig Danzer (OberWolfach photo collection) The story I am going to tell here was told in several places, but it might be new to some readers and I will mention my own angle, … Continue reading
Posted in Combinatorics, Convex polytopes, Geometry, Open problems
Tagged Joseph Zaks, Micha A. Perles
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Where were we?
I was slow blogging, and catching up won’t be so easy. Of course, this brings me back to the question of what I should blog about. Ideally, I should tell you about mathematical things I heard about. The problem is … Continue reading