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arXiv · 1512.08365

The Module Isomorphism Problem for Finite Rings and Related Results

Iuliana Ciocănea-Teodorescu
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Abstract

Let $R$ be a finite ring and let $M, N$ be two finite left $R$-modules. We present two distinct deterministic algorithms that decide in polynomial time whether or not $M$ and $N$ are isomorphic, and if they are, exhibit an isomorphism. As by-products, we are able to determine the largest isomorphic common direct summand between two modules and the minimum number of generators of a module. By not requiring $R$ to contain a field, avoiding computation of the Jacobson radical and not distinguishing between large and small characteristic, both algorithms constitute improvements to known results.

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Iuliana Ciocănea-Teodorescu. 2015-12-28. The Module Isomorphism Problem for Finite Rings and Related Results. https://arxiv.org/abs/1512.08365

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