Ώρα: 11:00
Αίθουσα: Γ31

Ομιλητής: Filip Jevtić, Mathematical Institute of the Serbian Academy of Sciences and Arts

Τίτλος: Bier Spheres

Περίληψη: A Bier shpere is a simplicial complex defined as a deleted  join of a simplicial complex and its Alexander dual. It doesn't have  an a priori geometrical realization. Though combinatorially a shpere,  in most cases it is not polytopal. When is it polytopal? When is it  star-shaped? What is the volume of its geometrical realizations? What  is its connection with threshold complexes? How is it connected to  simple games? The results we'll show (partially) answer these  questions and are a product of joint works with M. Timotijević and  R.T. Živaljević.