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- Giving a talk at Eli and Ricky’s geometry seminar. (October 19, 2021)
- To cheer you up in difficult times 32, Annika Heckel’s guest post: How does the Chromatic Number of a Random Graph Vary?
- To Cheer You Up in Difficult Times 31: Federico Ardila’s Four Axioms for Cultivating Diversity
- 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

### Top Posts & Pages

- Giving a talk at Eli and Ricky's geometry seminar. (October 19, 2021)
- Academic Degrees and Sex
- The Argument Against Quantum Computers - A Very Short Introduction
- To cheer you up in difficult times 32, Annika Heckel's guest post: How does the Chromatic Number of a Random Graph Vary?
- To Cheer You Up in Difficult Times 31: Federico Ardila's Four Axioms for Cultivating Diversity
- To cheer you up in difficult times 11: Immortal Songs by Sabine Hossenfelder and by Tom Lehrer
- TYI 30: Expected number of Dice throws
- Richard Stanley: How the Proof of the Upper Bound Theorem (for spheres) was Found
- Must-read book by Avi Wigderson

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# Monthly Archives: February 2015

## Combinatorics and More – Greatest Hits

Combinatorics and More’s Greatest Hits First Month Combinatorics, Mathematics, Academics, Polemics, … Helly’s Theorem, “Hypertrees”, and Strange Enumeration I (There were 3 follow up posts:) Extremal Combinatorics I: Extremal Problems on Set Systems (There were 4 follow up posts II ; III; IV; VI) Drachmas Rationality, Economics and … Continue reading

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## Ilan and me

With Ilan, my four month old grandson

## The Simplex, the Cyclic polytope, the Positroidron, the Amplituhedron, and Beyond

A quick schematic road-map to these new geometric objects. The positroidron can be seen as a cellular structure on the nonnegative Grassmanian – the part of the real Grassmanian G(m,n) which corresponds to m by n matrices with all m by … Continue reading

## From Oberwolfach: The Topological Tverberg Conjecture is False

The topological Tverberg conjecture (discussed in this post), a holy grail of topological combinatorics, was refuted! The three-page paper “Counterexamples to the topological Tverberg conjecture” by Florian Frick gives a brilliant proof that the conjecture is false. The proof is … Continue reading

Posted in Combinatorics, Conferences, Convexity, Updates
Tagged Florian Frick, Issac Mabillard, Oberwolfach, Uli Wagner
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