# Alex Cohen “Equivalence of 3-tensor ranks” | Big Seminar

May 6, 2021
19.00 MSK (UTC +3)
Talk on Big Seminar

# Alex Cohen "Equivalence of 3-tensor ranks"

Alex Cohen from Yale University, US will give the talk "Equivalence of 3-tensor ranks" on the labs' Big Seminar.

The talk will be held in zoom
Password: first 6 decimal places of $\pi$ after the decimal point

You can also write to Alexander Polyanskii (alexander.polyanskii@yandex.ru) or to Maksim Zhukovskii (zhukmax@gmail.com) if you want to be added to mailing list.

Abstract:

We prove that the slice rank of a 3-tensor (a combinatorial notion introduced by Tao in the context of the cap-set problem), the analytic rank (a Fourier-theoretic notion introduced by Gowers and Wolf), and the geometric rank (a recently introduced algebro-geometric notion) are all equivalent up to an absolute constant. The proof uses tools from algebraic geometry to argue about tangent spaces to certain determinantal varieties corresponding to the tensor. Our result settles open questions of Haramaty and Shpilka [STOC 2010], and of Lovett [Discrete Anal., 2019] for 3-tensors.

Joint work with Guy Moshkovitz.

## Watch the video:

Everyone is invited to attend. The language of the lecture is English. The event is aimed at master and graduate students, as well as researchers in the field of combinatorics.