Geodesic
Amalgamations of Categories
Canadian mathematical bulletin, Tome 52 (2009) no. 2, pp. 273-284

Voir la notice de l'article provenant de la source Cambridge University Press

We consider the pushout of embedding functors in Cat, the category of small categories. We show that if the embedding functors satisfy a 3-for-2 property, then the induced functors to the pushout category are also embeddings. The result follows from the connectedness of certain associated slice categories. The condition is motivated by a similar result for maps of semigroups. We show that our theorem can be applied to groupoids and to inclusions of full subcategories. We also give an example to show that the theorem does not hold when the property only holds for one of the inclusion functors, or when it is weakened to a one-sided condition.
DOI : 10.4153/CMB-2009-030-5
Mots-clés : 18A30, 18B40, 20L17, category, pushout, amalgamation 
MacDonald, John; Scull, Laura. Amalgamations of Categories. Canadian mathematical bulletin, Tome 52 (2009) no. 2, pp. 273-284. doi: 10.4153/CMB-2009-030-5
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