In the previous blog post, one of us (Terry) implicitly introduced a notion of rank for tensors which is a little different from the usual notion of tensor rank, and which (following… 3,914 more words

In the previous blog post, one of us (Terry) implicitly introduced a notion of rank for tensors which is a little different from the usual notion of tensor rank, and which (following… 3,914 more words

In a previous post I discussed how the Alon-Furedi theorem serves as a common generalisation of the results of Schwartz, DeMillo, Lipton and Zippel. Here I will show some nice applications of this theorem to finite geometry (reference: Section 6 of… 973 more words

A *capset* in the vector space over the finite field of three elements is a subset of that does not contain any lines , where and . 1,355 more words

Jordan Ellenberg has just announced a resolution of the “cap problem” using techniques of Croot, Lev and Pach, in a self-contained three-page paper. This is a quite unexpected development for a long-standing open problem in the core of additive combinatorics. 787 more words

Four days back Jordan Ellenberg posted the following on his blog:

1,076 more wordsBriefly: it seems to me that the idea of the Croot-Lev-Pach paper I posted about yesterday…

As you know I love the affine cap problem: how big can a subset of (Z/3Z)^n be that contains no three elements summing to 0 — or, in other words, that contains no 3-term arithmetic progression? 840 more words

*Let be a sequence of integers (not necessarily distinct). Then there exists a subsequence of the sum of whose elements is divisible by . *

This is one of the first problems I saw when learning the… 658 more words