- AlexFest: 60 Faces of Groups
- Postoctoral Positions with Karim and Other Announcements!
- AviFest, AviStories and Amazing Cash Prizes.
- Polymath 10 post 6: The Erdos-Rado sunflower conjecture, and the Turan (4,3) problem: homological approaches.
- Polymath 10 Emergency Post 5: The Erdos-Szemeredi Sunflower Conjecture is Now Proven.
- Mind Boggling: Following the work of Croot, Lev, and Pach, Jordan Ellenberg settled the cap set problem!
- More Math from Facebook
- The Erdős Szekeres polygon problem – Solved asymptotically by Andrew Suk.
Top Posts & Pages
- Extremal Combinatorics IV: Shifting
- Extremal Combinatorics III: Some Basic Theorems
- Polymath10: The Erdos Rado Delta System Conjecture
- A Breakthrough by Maryna Viazovska Leading to the Long Awaited Solutions for the Densest Packing Problem in Dimensions 8 and 24
- My Book: "Gina Says," Adventures in the Blogosphere String War
- The Simplex, the Cyclic polytope, the Positroidron, the Amplituhedron, and Beyond
- Answer: Lord Kelvin, The Age of the Earth, and the Age of the Sun
- Happy Birthday Richard Stanley!
- Gina Says Part two
Monthly Archives: June 2009
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,’ 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
I wrote a book. It is a sort of a popular science book and it is also about blogging and debating. You can download the first part of the book : It is a 94 page pdf file. “Gina Says,” Adventures in … Continue reading
Jeff Kahn Jeff and I worked on the problem for several years. Once he visited me with his family for two weeks. Before the visit I emailed him and asked: What should we work on in your visit? Jeff asnwered: … Continue reading
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
Are you aware of any? (current ones? old ones?)
(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?
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