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- Giving a talk at Eli and Ricky’s geometry seminar. (October 19, 2021)
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- Dream a Little Dream: Quantum Computer Poetry for the Skeptics (Part I, mainly 2019)
- To Cheer you up in difficult times 30: Irit Dinur, Shai Evra, Ron Livne, Alex Lubotzky, and Shahar Mozes Constructed Locally Testable Codes with Constant Rate, Distance, and Locality
- To cheer you up in difficult times 29: Free will, predictability and quantum computers
- Alef’s corner: Mathematical research
- Let me tell you about three of my recent papers
- Mathematical news to cheer you up

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- Giving a talk at Eli and Ricky's geometry seminar. (October 19, 2021)
- Academic Degrees and Sex
- Answer: Lord Kelvin, The Age of the Earth, and the Age of the Sun
- The Argument Against Quantum Computers - A Very Short Introduction
- To Cheer You Up in Difficult Times 31: Federico Ardila's Four Axioms for Cultivating Diversity
- Richard Stanley: How the Proof of the Upper Bound Theorem (for spheres) was Found
- To cheer you up in difficult times 32, Annika Heckel's guest post: How does the Chromatic Number of a Random Graph Vary?
- Amazing: Karim Adiprasito proved the g-conjecture for spheres!
- TYI 30: Expected number of Dice throws

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# Monthly Archives: June 2009

## Test Your Intuition (6)

This is not as clear cut a question as the earlier ones, and if you do not know an answer then it will be difficult to figure one out just based on intuition. (But perhaps possible). If you are intrigued by … Continue reading

## Praise For ‘Gina says’

Praise for: ” ‘Gina Says,’ Adventures in the Blogsphere String War (Below the dividing line: Greg Kuperberg, Scott Aaronson, Clifford Johnson, Peter Woit, Motty Perry, Caterina Calsamiglia, Yuval Peres, Eva Illouz, and (right from the comment section) Luca Trevisan, Thomas … Continue reading

Posted in Book review, Gina Says
11 Comments

## My Book: “Gina Says,” Adventures in the Blogosphere String War

Update (November 2017): I received an advanced copy. How exciting! Update (October 2017): The much changed version of the book with beautiful drawing by my daughter Neta Kalai is soon to appear in print. It is published by World Scientific. Here … Continue reading

Posted in Blogging, Gina Says
36 Comments

## Borsuk’s Conjecture

Karol Borsuk conjectured in 1933 that every bounded set in can be covered by sets of smaller diameter. Jeff Kahn and I found a counterexample in 1993. It is based on the Frankl-Wilson theorem. Let be the set of vectors of length . … Continue reading

## Banknotes with Pictures of Mathematicians

Are you aware of any? (current ones? old ones?)

Posted in Uncategorized
12 Comments

## Test Your Intuition (5)

(Not such a set) consider a planar set A with the following property. In every direction, the distance between the two parallel lines that touch A from both sides is the same! Must A be a circle?

## Answer To Test Your Intuition (4)

Let G be a graph and u and v two vertices. (1) Let H be a random graph where every edge of G is chosen with probability ½. Let p be the probability that there is a path between u … Continue reading

## Test Your Intuition (4)

Posted in Probability
18 Comments