A Note on Double Central Extensions in Exact Mal’tsev Categories
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چکیده
The characterisation of double central extensions in terms of commutators due to Janelidze (in the case of groups), Gran and Rossi (in the case of Mal’tsev varieties) and Rodelo and Van der Linden (in the case of semi-abelian categories) is shown to be still valid in the context of exact Mal’tsev categories.
منابع مشابه
A NOTE ON DOUBLE CENTRAL EXTENSIONS IN EXACT MAL’TSEV CATEGORIES dedicated to Francis Borceux on the occasion of his sixtieth birthday
La caractérisation des extensions centrales doubles en termes de commutateurs de Janelidze (dans le cas des groupes) et de Gran et Rossi (dans le cas des variétés de Mal’tsev) est montrée d’être toujours valide dans le contexte des catégories exactes de Mal’tsev avec coégalisateurs. The characterisation of double central extensions in terms of commutators due to Janelidze (in the case of groups...
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تاریخ انتشار 2009