On some categories of triangular norms on the real unit interval

Document Type : Research Paper


Institute of Mathematics, University of Silesia in Katowice, Katowice, Poland


In this work, we introduce some categories of triangular norms in which truth values belong to the real unit interval, where arrows are a generalization of automorphisms. We investigate the existence of products, coproducts, equalizers and  coequalizers in these categories. Moreover, we show that Theorems 2.29, 2.30 in \cite{Yousefi_Mashinchi_Mesiar_2021} are false by providing counterexamples.


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