Shuffle algebras, lattice paths and the commuting scheme
Abstract
The commutative trigonometric shuffle algebra ${\mathrm A}$ is a space of symmetric rational functions satisfying certain wheel conditions. We describe a ring isomorphism between ${\mathrm A}$ and the center of the Hecke algebra using a realization of the elements of ${\mathrm A}$ as partition functions of coloured lattice paths associated to the $R$matrix of $\mathcal U_{t^{1/2}}(\widehat{gl}_{\infty})$. As an application, we compute under certain conditions the Hilbert series of the commuting scheme and identify it with a particular element of the shuffle algebra ${\mathrm A}$, thus providing a combinatorial formula for it as a "domain wall" type partition function of coloured lattice paths.
 Publication:

arXiv eprints
 Pub Date:
 October 2021
 arXiv:
 arXiv:2110.07155
 Bibcode:
 2021arXiv211007155G
 Keywords:

 Mathematics  Representation Theory;
 Mathematical Physics;
 Mathematics  Algebraic Geometry