Relative Approximations and Maschke functors

نویسنده

  • Bin Zhu
چکیده

The notion of approximations relative to a functor is introduced and several characterizations of relative (dual) Maschke functors are given by using them. As an application, the injective objects in the category of comodules over a coring are described.

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تاریخ انتشار 2003