Author Archives: Gil Kalai

Mathematical news to cheer you up

1.  Anna Kiesenhofer, a PhD mathematician researching PDEs at Ecole Polytechnique Federale Lausanne (EPFL), won the gold medal in the women’s bicycle road race at the Olympics. Here are two trivia question: a) Which hero of a recent post over … Continue reading

Posted in Combinatorics, Sport, Uncategorized, Updates | 3 Comments

To Cheer You Up in Difficult Times 28: Math On the Beach (Alef’s Corner)

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To cheer you up in difficult times 27: A major recent “Lean” proof verification

“Lean is a functional programming language that makes it easy to write correct and maintainable code. You can also use Lean as an interactive theorem prover.” (See Lean’s homepage and see here for an introduction to lean.) Kevin Buzzard’s blog … Continue reading

Posted in Algebra, Updates, What is Mathematics | Tagged , , | 4 Comments

To cheer you up in difficult times 26: Two real-life lectures yesterday at the Technion

After 16 months without lecturing to an audience in my same location, I gave yesterday two lectures at the Technion in front of a live audience (and some additional audience in remote locations). The main lecture was in COMSOC 2021, … Continue reading

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To Cheer You Up in Difficult times 24: Borodin’s colouring conjecture!

An acyclic colouring of a graph is a colouring of its vertices so that the subgraph spanned on union of every two colour classes is acyclic (a forest). Grunbaum conjectured in 1973 that Every planar graph has acyclic colouring with … Continue reading

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To cheer you up in difficult times 25: some mathematical news! (Part 2)

Topology Quasi-polynomial algorithms for telling if a knot is trivial Marc Lackenby announced a quasi-polynomial time algorithm to decide whether a given knot is the unknot! This is a big breakthrough. This question is known to be both in NP … Continue reading

Posted in Algebra, Combinatorics, Geometry, Number theory | 2 Comments

To cheer you up in difficult times 23: the original hand-written slides of Terry Tao’s 2015 Einstein Lecture in Jerusalem

In 2015 Terry Tao gave the Einstein lecture of the Israeli Academy for Science and Humanities. We got hold of the original signed hand-written slides of Terry’s lecture and we are happy to share them with you. The title of … Continue reading

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Alef Corner: ICM2022

Alef’s new piece for ICM 2022 will surely cheer you up!

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The probabilistic proof that 2^400-593 is a prime: a revolutionary new type of mathematical proof, or not a proof at all?

Avi Wigderson gave a great CS colloquium talk at HUJI on Monday (a real auditorium talk with an audience of about 200 people). The title of the talk was The Value of Errors in Proofs – a fascinating journey from … Continue reading

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With Avi at Suzanna

To cheer you up even further a new story that breaks new ground about Avi Wigderson and me (and Laci Lovasz) and a couple more famous Isrealis. For another story about Avi and me see Layish. (I told both stories … Continue reading

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