# Prof. dr. Alexander Mednykh: Counting coverings and maps

Date of publication: 17. 4. 2011

Mathematics colloquium

Četrtek, 21. 4. 2011, ob 16:15 v predavalnici 2.02 na Jadranski 21.

Prof. dr. Alexander Mednykh

Sobolev Institute of Mathematics

Novosibirsk State University

Novosibirsk State University

In this lecture we give a new method to count finite sheeted coverings of manifolds with a finitely generated fundamental group. We apply it to count branched and unbranched coverings over compact surfaces (bordered or with empty border).

As a consequence, we suggest a new approach to count maps on surfaces up to orientation preserving homeomorphism. The further development of the method gives us a possibility to count chiral maps (or twins) by number of edges on a closed orientable surface.