Hilbert Basis Theorem and Finite Generation of Invariants in Symmetric Fusion Categories in Positive Characteristic

TL;DR

This paper extends the Hilbert basis theorem and finite generation of invariants to symmetric finite tensor categories over fields of positive characteristic, proving the conjecture in specific cases and constructing a new candidate supervector space category.

Contribution

It conjectures and proves the extension of classical invariant theory results to positive characteristic tensor categories, introducing a new supervector space category in characteristic 2.

Findings

Proved the conjecture for semisimple categories.

Constructed a symmetric finite tensor category $ ext{sVec}_2$ in characteristic 2.

Showed $ ext{sVec}_2$ does not fiber over the Verlinde category of $SL_2$.

Abstract

In this paper, we conjecture an extension of the Hilbert basis theorem and the finite generation of invariants to commutative algebras in symmetric finite tensor categories over fields of positive characteristic. We prove the conjecture in the case of semisimple categories and more generally in the case of categories with fiber functors to the characteristic $p > 0$ Verlinde category of $SL_{2}$. We also construct a symmetric finite tensor category $\sVec_{2}$ over fields of characteristic $2$ and show that it is a candidate for the category of supervector spaces in this characteristic. We further show that $\sVec_{2}$ does not fiber over the characteristic $2$ Verlinde category of $SL_{2}$ and then prove the conjecture for any category fibered over $\sVec_{2}$.