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1. • CommentRowNumber1.
   • CommentAuthorUrs
   • CommentTimeAug 19th 2020
   • PermaLink
   Author: Urs
   Format: MarkdownItexstarting a `category:reference`-entry for this book by Gelfand & Manin <a href="https://ncatlab.org/nlab/revision/Methods+of+homological+algebra/1">v1</a>, <a href="https://ncatlab.org/nlab/show/Methods+of+homological+algebra">current</a>

   starting a category:reference-entry for this book by Gelfand & Manin

   v1, current

2. • CommentRowNumber2.
   • CommentAuthorUrs
   • CommentTimeAug 20th 2020
   • (edited Aug 20th 2020)
   • PermaLink
   Author: Urs
   Format: MarkdownItexThe following seems to be a mistake in _[[Methods of homological algebra|Gelfand-Manin 96]]_: on p. 335 they claim that the ground field is the terminal object in dgc-algebras. That would be true for augmented algebras, which is however not what they are discussing at this point. The terminal object is the zero-algebra. And maybe they misled themselves by the way they are defining unital algebras on p. 333.

   The following seems to be a mistake in Gelfand-Manin 96:

   on p. 335 they claim that the ground field is the terminal object in dgc-algebras.

   That would be true for augmented algebras, which is however not what they are discussing at this point. The terminal object is the zero-algebra. And maybe they misled themselves by the way they are defining unital algebras on p. 333.