In this paper we give a short and simple proof the following theorem of S. Eilenberg and J.C. Moore: the only injective object in the category of groups is the trivial group.
@article{bwmeta1.element.doi-10_2478_s11533-006-0040-7, author = {Maria Nogin}, title = {A short proof of Eilenberg and Moore's theorem}, journal = {Open Mathematics}, volume = {5}, year = {2007}, pages = {201-204}, zbl = {1120.20054}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.doi-10_2478_s11533-006-0040-7} }
Maria Nogin. A short proof of Eilenberg and Moore’s theorem. Open Mathematics, Tome 5 (2007) pp. 201-204. http://gdmltest.u-ga.fr/item/bwmeta1.element.doi-10_2478_s11533-006-0040-7/
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