Following Ghilardi and Meloni, a relational variable set on a category B is a lax functor B to Rel, where Rel is the category of sets and relations. Change-of-base functors and their adjoints are considered for certain categories of relational variable sets and applied to construct the simplification of a dynamic set (in the sense of Stell).
Keywords: relational variable set, specification structure, dynamic set, relational presheaf, change of base, exponentiable
2000 MSC: 18A40, 08A02, 18F20, 18A22
Theory and Applications of Categories,
Vol. 12, 2004,
No. 7, pp 248-261.
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