We prove that certain categories arising from atoms in a Grothendieck topos are themselves Grothendieck toposes. We also investigate enrichments of these categories over the base topos; there are in fact often two distinct enrichments.
Keywords: atom, coalgebra, enrichment.
1991 MSC: 18B25,18D20.
Theory and Applications of Categories, Vol. 5, 1999, No. 10, pp 251-265.
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