On Composition Tableaux basis for the Pl\"ucker algebra
Shubhankar Sahai · arXiv (Cornell University) · 2018
Let $V$ be a complex vector space with $\textrm{dim}_{\mathbb{C}}(V)=n$. The irreducible polynomial representations of $\textrm{GL}(V)$ are the Schur Functors $\mathbb{S}^{\lambda}(V)$, with each Schur Functors labelled by a partition with parts atmost $n$. The representations can be realized inside a certain subring of the polynomial ring $\mathbb{C}[z_{i,j}]$ in $n^2$ variables. This subring , $\Pi$, is called the Plucker Algebra and has a decomposition into irreducible $\textrm{GL}(V)$ representations as $\Pi \cong \bigoplus\mathbb{S}^{\lambda}(V)$. In \cite{mason}, Mason and Remmel introduce Row Strict Composition Tableaux (RSCT), a method of filling composition diagrams, which are diagrams associated to compositions of positive integers. This gives a method of realization of the Plucker Algebra by taking associated minors of the matrix in $n^2$ indeterminates. In this paper, we develop the representation theory of these RSCT fillings. For each Schur Functor $\mathbb{S}^{\lambda}(V)$, we identify certain compositions, and show that the polynomials that one gets from the minors associated to the RSCT fillings of these compositions, form a basis for that Schur Functor inside $\Pi$.