Deformation cone of Tesler polytopes (2212.11423v2)

Abstract: For $\boldsymbol{a} \in \R_{\geq 0}^{n}$, the Tesler polytope $\tes_{n}(\boldsymbol{a})$ is the set of upper triangular matrices with non-negative entries whose hook sum vector is $\ba$. We first give a different proof of the known fact that for every fixed $\boldsymbol{a}{0} \in \mathbb{R}{>0}^{n}$, all the Tesler polytopes $\tes_{n}(\boldsymbol{a})$ are deformations of $\tes_{n}(\boldsymbol{a}{0})$. We then calculate the deformation cone of $\tes{n}(\boldsymbol{a}{0})$. In the process, we also show that any deformation of $\tes{n}(\boldsymbol{a}{0})$ is a translation of a Tesler polytope. Lastly, we consider a larger family of polytopes called flow polytopes which contains the family of Tesler polytopes and give a characterization on which flow polytopes are deformations of $\tes{n}(\boldsymbol{a}_{0})$.