Browsing by Author "Grinberg, Darij"

Now showing items 1-5 of 5

    • Birational Rowmotion on a Rectangle over a Noncommutative Ring 

      [OWP-2022-17] Grinberg, Darij; Roby, Tom (Mathematisches Forschungsinstitut Oberwolfach, 2022-09-20)
      We extend the periodicity of birational rowmotion for rectangular posets to the case when the base field is replaced by a noncommutative ring (under appropriate conditions). This resolves a conjecture from 2014. The proof ...

    • The Elser Nuclei Sum Revisited 

      [OWP-2021-05] Grinberg, Darij (Mathematisches Forschungsinstitut Oberwolfach, 2021-03-16)
      Fix a finite undirected graph $\Gamma$ and a vertex $v$ of $\Gamma$. Let $E$ be the set of edges of $\Gamma$. We call a subset $F$ of $E$ $\textit{pandemic}$ if each edge of $\Gamma$ has at least one endpoint that can be ...

    • Hopf Algebras in Combinatorics, Volume 1 

      [OWP-2020-14] Grinberg, Darij; Reiner, Victor (Mathematisches Forschungsinstitut Oberwolfach, 2020-07-29)

    • Hopf Algebras in Combinatorics, Volume 2 

      [OWP-2020-15] Grinberg, Darij; Reiner, Victor (Mathematisches Forschungsinstitut Oberwolfach, 2020-07-30)

    • The Pelletier-Ressayre Hidden Symmetry for Littlewood-Richardson Coefficients 

      [OWP-2020-18] Grinberg, Darij (Mathematisches Forschungsinstitut Oberwolfach, 2020-09-08)
      We prove an identity for Littlewood–Richardson coefficients conjectured by Pelletier and Ressayre. The proof relies on a novel birational involution defined over any semifield.