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arXiv · 2305.00587

Additively idempotent matrix semirings

Tomáš Kepka·Miroslav Korbelář
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Abstract

Let $S$ be an additively idempotent semiring and $\mathbf{M}_n(S)$ be the semiring of all $n\times n$ matrices over $S$. We characterize the conditions of when the semiring $\mathbf{M}_n(S)$ is congruence-simple provided that the semiring $S$ is either commutative or finite. We also give a characterization of when the semiring $\mathbf{M}_n(S)$ is subdirectly irreducible for $S$ beeing almost integral (i.e., $xy+yx+x=x$ for all $x,y\in S$). In particular, we provide this characterization for the semirings $S$ derived from the pseudo MV-algebras.

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Tomáš Kepka, Miroslav Korbelář. 2023-04-30. Additively idempotent matrix semirings. https://arxiv.org/abs/2305.00587

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