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- What is mathematics (or at least, how it feels)
- Alef’s Corner
- To cheer you up in difficult times 22: some mathematical news! (Part 1)
- Cheerful News in Difficult Times: The Abel Prize is Awarded to László Lovász and Avi Wigderson
- Amazing: Feng Pan and Pan Zhang Announced a Way to “Spoof” (Classically Simulate) the Google’s Quantum Supremacy Circuit!
- To cheer you up in difficult times 21: Giles Gardam lecture and new result on Kaplansky’s conjectures
- Nostalgia corner: John Riordan’s referee report of my first paper
- At the Movies III: Picture a Scientist
- At the Movies II: Kobi Mizrahi’s short movie White Eye makes it to the Oscar’s short list.
Top Posts & Pages
- To cheer you up in difficult times 21: Giles Gardam lecture and new result on Kaplansky's conjectures
- To cheer you up in difficult times 5: A New Elementary Proof of the Prime Number Theorem by Florian K. Richter
- Amazing: Simpler and more general proofs for the g-theorem by Stavros Argyrios Papadakis and Vasiliki Petrotou, and by Karim Adiprasito, Stavros Argyrios Papadakis, and Vasiliki Petrotou.
- Are Natural Mathematical Problems Bad Problems?
- Cheerful News in Difficult Times: The Abel Prize is Awarded to László Lovász and Avi Wigderson
- The Argument Against Quantum Computers - A Very Short Introduction
- What is mathematics (or at least, how it feels)
- TYI 30: Expected number of Dice throws
- To cheer you up in difficult times 17: Amazing! The Erdős-Faber-Lovász conjecture (for large n) was proved by Dong Yeap Kang, Tom Kelly, Daniela Kühn, Abhishek Methuku, and Deryk Osthus!
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Tag Archives: Geometric combinatorics
Coloring Problems for Arrangements of Circles (and Pseudocircles)
To supplement and celebrate Aubrey de Grey’s result here are Eight problems on coloring circles A) Consider a finite family of unit circles. What is the minimum number of colors needed to color the circles so that tangent circles are … Continue reading
Posted in Combinatorics, Geometry, Open problems
Tagged Geometric combinatorics, geometric graphs, Graph-coloring
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A Discrepancy Problem for Planar Configurations
Yaacov Kupitz and Micha A. Perles asked: What is the smallest number C such that for every configuration of n points in the plane there is a line containing two or more points from the configuration for which the difference between the … Continue reading
Extremal Combinatorics II: Some Geometry and Number Theory
Extremal problems in additive number theory Our first lecture dealt with extremal problems for families of sets. In this lecture we will consider extremal problems for sets of real numbers, and for geometric configurations in planar Euclidean geometry. Problem I: Given a set A of … Continue reading