Enriched category

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Definition

Suppose M is a monoidal category. A category enriched in M is defined as a C equipped with the following data:

  • A collection of objects ObC.
  • For any objects A,BObC, an object C(A,B)ObM.
  • For any object AObC, a unit map uA from the unit object in M to C(A,A).
  • For any objects A,B,CObC, a morphism in M:

:C(B,C)C(A,B)C(A,C)

where denotes the monoidal operation on M.

satisfying the following conditions:

  • For any A,B,C,DObC, with fC(A,B),gC(B,C),hC(C,D), we have h(gf)=(hg)f.
  • For any A,BObC, the map :C(B,B)C(A,B)C(A,B), composed with uB on the first coordinate, gives the identity map on the second coordinate. Similarly, the other way around. Need to make more precise -- Fill this in later