On descent for coalgebras and type transformations | ||
| Categories and General Algebraic Structures with Applications | ||
| مقاله 5، دوره 5، شماره 1، مهر 2016، صفحه 103-130 اصل مقاله (249.73 K) | ||
| نوع مقاله: Research Paper | ||
| نویسنده | ||
| Maurice Kianpi | ||
| Laboratory of Algebra, Geometry and Applications, Department of Mathematics, Faculty of Science, University of Yaounde 1, P.O. Box 812, Yaounde, Republic of Cameroon. | ||
| چکیده | ||
| We find a criterion for a morphism of coalgebras over a Barr-exact category to be effective descent and determine (effective) descent morphisms for coalgebras over toposes in some cases. Also, we study some exactness properties of endofunctors of arbitrary categories in connection with natural transformations between them as well as those of functors that these transformations induce between corresponding categories of coalgebras. As a result, we find conditions under which the induced functors preserve natural number objects as well as a criterion for them to be exact. Also this enable us to give a criterion for split epis in a category of coalgebras to be effective descent. | ||
| کلیدواژهها | ||
| category؛ functor؛ coalgebra؛ natural transformation؛ (co)limits؛ (effective) descent morphism | ||
| مراجع | ||
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