On **March 3, 2022** the Faculty of Fundamental Sciences of Bauman Moscow State Technical University will held the fourth meeting of the Scientific Workshop "**BMSTU Mathematical Colloquium**".

It addresses a broad mathematical audience including keen students.

The workshop will be held on **Thursday at 5:30 pm**, ZOOM, meeting id: 874 2859 2359, password: E1Tc85

https://us02web.zoom.us/j/87428592359?pwd=a2ROWXBEMkwvT0VITHk0NVFiU1ROdz09

The workshop topic: **Topological isotopy and Cochran's invariants of links**

The report will be given by **Melikhov Sergey Aleksandrovich (Steklov Mathematical Institute of Russian Academy of Sciences)**

**Abstract:** We show that there exists a 2-component link in the 3-space that is not isotopic (i.e. not homotopic through embeddings) to any smooth (or piecewise linear) link. The proof is unusually visual and is based on Cochran's invariants. The similar question for 1-component links, that is, knots is a well-known problem of Rolfsen (1974) which remains open. We will also discuss what else is known about isotopy and about Cochran's invariants.

The details are available in https://arxiv.org/abs/2011.01409

*If you are going to come or with any questions, please write to e-mail: *This email address is being protected from spambots. You need JavaScript enabled to view it.u