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arXiv · 1701.08859

Jordan Isomorphisms of Finitary Incidence Algebras

Rosali Brusamarello·Érica Z. Fornaroli·Mykola Khrypchenko
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Abstract

Let $X$ be a partially ordered set, $R$ a commutative $2$-torsionfree unital ring and $FI(X,R)$ the finitary incidence algebra of $X$ over $R$. In this note we prove that each $R$-linear Jordan isomorphism of $FI(X,R)$ onto an $R$-algebra $A$ is the near-sum of a homomorphism and an anti-homomorphism.

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Rosali Brusamarello, Érica Z. Fornaroli, Mykola Khrypchenko. 2017-03-06. Jordan Isomorphisms of Finitary Incidence Algebras. https://arxiv.org/abs/1701.08859

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