Dear Friends of Hikes and Mathematics,

you are invited to our 28th mathematical hike planned on January 25th. Meet at 09:36 at the bus stop "Veverská Bítýška, náměstí" (bus number 303).

The hike is 18 km long - we will follow a green path to Lažánky and go a full circle by a yellow path to Bítýška. We will return to Brno by bus.

All information and photos can be found at http://conference.math.muni.cz/vylety/. (in CZ)

Have a nice January and successful exam period,

Jonatan Kolegar and Jana Bartoňová, organizers,
Jan Slovák, Director of the Department of Mathematics and Statistics

We will continue on Thursday, January 9, in M5 at 1pm by the talk

S. Henry

Polygraphs and homotopy polygraphs

Abstract:
Polygraphs (or computades) are the most general notion of diagram generating strict infinity categories. Some people have believed in the past that they were a presheaves category, but this was proved to be false by Makkai and Zawadowski.
After a quick introduction to polygraphs and why they are not a presheaves category, I'll show that if one defines a homotopy theoretic (or infinity categorical) version of polygraphs then they form an infinity presheaves category. More generally I'll associate to any strongly cartesian monad acting on an infinity topos an infinity category of polygraphs which is itself an infinity topos.

December 18, 2019 from 4:30 PM at Refectory of Augustinian Abbey at Mendel Square - Mendel Museum

Noga Alon

List Coloring

Abstract:

The list chromatic number of a graph G is the minimum k so that for every assignment of a list of k colors to any vertex of G there is a vertex coloring assigning to each vertex a color from its list so that adjacent vertices get distinct colors. This notion was introduced by Vizing and by Erdős, Rubin and Taylor in the late 70s and its study combines combinatorial, probabilistic and algebraic techniques.

Its natural extension to hypergraphs is closely related to questions in Euclidean Ramsey Theory.

I will discuss several old and new problems and results in the area focusing on a recent work with Briceno, Chandgotia, Magazinov and Spinka motivated by questions in statistical physics regarding vertex colorings of the d-dimensional lattice.

Dear Friends of Hikes and Mathematics,

you are invited to our 27th mathematical hike planned on December 14th. Meet at 09:36 at the bus stop "Rozcestí" (bus 57) in Útěchov.

We have planned a short hike (not even 10 km) not following any tourist path towards the ruins of Ronov castle. The end of the hike is in Útěchov.

Snow or mud, doesn't matter, look forward to a Christmas hike.

All information and photos can be found at http://conference.math.muni.cz/vylety/. (in CZ)

Have a nice December,

Jonatan Kolegar and Jana Bartoňová, organizers,
Jan Slovák, Director of the Department of Mathematics and Statistics