منابع مشابه
Van Kampen theorems for toposes
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Colimits that satisfy the Van Kampen condition have interesting exactness properties. We show that the elementary presentation of the Van Kampen condition is actually a characterisation of a universal property in the associated bicategory of spans. The main theorem states that Van Kampen cocones are precisely those diagrams in a category that induce bicolimit diagrams in its associated bicatego...
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In adhesive categories, pushouts along monomorphisms are Van Kampen (vk) squares, a special case of a more general notion called vk-diagram. Other examples of vk-diagrams include coproducts in extensive categories and strict initial objects. Extensive and adhesive categories characterise useful exactness properties of, respectively, coproducts and pushouts along monos and have found several app...
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ژورنال
عنوان ژورنال: Tidsskrift for Den norske legeforening
سال: 2010
ISSN: 0029-2001
DOI: 10.4045/tidsskr.10.0109