Monday, July 7, 2015
(ZIB) Konrad-Zuse-Zentrum für Informationstechnik Berlin
Takustr. 7
14195 Berlin
Lecture hall
Lecture - 14:00 (s.t.)
Abstract:
The talk is the first one in the identically entitled lecture series given at the BMS summer school "Convex geometry - discrete and computational" .
It will survey on results and methods presented in the course
Convex geometry - discrete and computational
Colloquium - 16:00
Location:
Freie Universität Berlin
Takustr. 9
14195 Berlin
Hörsaal der Informatik
Abstract:
This talk deals with the sets of flag vectors of convex $4$-polytopes and $3$-spheres.
After a short introduction to the main concepts, we will show that these sets differ.
In particular, we will examine a $3$-sphere $W_{12}^{40}$ with flag vector
$(f_0,f_1,f_2,f_3;f_{02})=(12,40,40,12;120)$:
we will show its non-polytopality via oriented matroids and its uniqueness with
the given flag vector via a complete enumeration of 2s2s $3$-spheres with up to $12$
vertices.
This is joint work with G. M. Ziegler.