Nested Frobenius extensions of graded superrings

TL;DR

This paper establishes a nesting property for twisted Frobenius extensions in graded superrings, showing that under certain conditions, an extension of a Frobenius extension remains Frobenius, generalizing previous results from fields to more general rings.

Contribution

It proves a new nesting theorem for twisted Frobenius extensions of graded superrings, extending prior results from fields to more general ring settings.

Findings

A nesting phenomenon for twisted Frobenius extensions is established.

Under specified conditions, A is a twisted Frobenius extension of B.

Generalizes previous results from fields to graded superrings.

Abstract

This paper is the result of a research project completed in the context of the first author's Undergraduate Student Research Award from the Natural Sciences and Engineering Research Council of Canada (NSERC). We prove a nesting phenomenon for twisted Frobenius extensions. Namely, suppose $R \subseteq B \subseteq A$ are graded superrings such that $A$ and $B$ are both twisted Frobenius extensions of $R$, $R$ is contained in the center of $A$, and $A$ is projective over $B$. Our main result is that, under these assumptions, $A$ is a twisted Frobenius extension of $B$. This generalizes a result of Pike and the second author, which considered the case where $R$ is a field.