Purity of extremal rays of Betti cones

H. Ananthnarayan, Omkar Javadekar, Rajiv Kumar

Let $R$ be a standard graded algebra over an infinite field $\mathsf{k}$, and let ${\mathbb{B}}_{\mathbb{Q}}(R)$ and ${\mathbb{B}}_{\mathbb{Q}}^{\mathrm{pure}}(R)$ denote the rational c…