Colloquium: Tuesday, December 4, 2018. Speaker: Eran Nevo (Hebrew University). Title: “Polytopes – from simplicial to non-simplicial”.

Department of Mathematics                                                           University of  Haifa




Speaker: Eran Nevo (Hebrew University)


Topic: Polytopes — from simplicial to non-simplicial


Place: Room 614 in the Education & Sciences Building

Time: 14:00

Date: Tuesday, December 4, 2018



A polytope is called simplicial if all its proper faces are simplices. The celebrated g-theorem gives a complete characterization of the possible face numbers (a.k.a. f-vector) of simplicial polytopes, conjectured by McMullen ’70 and proved by Billera-Lee (sufficiency) and by Stanley (necessity) ’80, the later uses deep relations with commutative algebra and algebraic geometry. Moving to general polytopes, a finer information than the f-vector is given by the flag-f-vector, counting chains of faces according to their dimensions. Here much less is known, or even conjectured. I will describe how the theory in the simplicial case reflects in the general case, and in subfamilies of interest, as well as open problems.

Tea will be served before the talk (at 13:50).