Intersections of reflective subcategories

Adámek, J.; Rosický, J.

doi:10.1090/S0002-9939-1988-0947643-9

Intersections of reflective subcategories
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by J. Adámek and J. Rosický PDF

Proc. Amer. Math. Soc. 103 (1988), 710-712 Request permission

Abstract:

It is shown that the class of full reflective subcategories of $\mathcal {Fq}$ (and of other concrete categories) is not closed under intersections. This answers a question raised by Herrlich in 1967. A natural example of nonreflective intersection is presented in the category of bitopological spaces.

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