Proper divisibility as a partially ordered set (*)

Room M005 - Department of Mahtematics - FCUP
Friday, 25 November, 2016 - 11:00

We define the order relation given by the proper divisibility of monomials, inspired by the definition of the Buchberger graph of a monomial ideal. From this order relation we obtain a new class of posets. Surprisingly, the order complexes of these posets are homologically non-trivial. We prove that these posets are dual CL-shellable, we completely describe their homology (with integer coefficients) and we compute their Euler characteristic. Moreover this order relation gives the first example of a dual CL-shellable poset that is not CL-shellable.

(*) joint work with Davide Bolognini, Emanuele Ventura and Volkmar Welker

Speaker: 

Antonio Macchia

Institution: 

University of Coimbra