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arXiv · 1604.08788

Nested Frobenius extensions of graded superrings

Edward Poon·Alistair Savage
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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.

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Edward Poon, Alistair Savage. 2016-04-29. Nested Frobenius extensions of graded superrings. https://doi.org/10.2140/involve.2018.11.449

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