Essential Weak Factorization Systems

نویسنده

  • Walter Tholen
چکیده

We discuss a new type of weak factorization system. Although these systems provide (up to isomorphism) uniquely determined decompositions of morphisms, in general they do not constitute orthogonal factorizations and are not even functorial. Nevertheless, they arise naturally, as injective hulls or projective covers in comma categories. Surprisingly, often injective hulls and projective covers coincide in this context.

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تاریخ انتشار 2007