Homeomorphism versus isomorphism for varieties
نویسندگان
چکیده
منابع مشابه
Cartier Isomorphism for Toric Varieties
is an isomorphism. Here F : X −→ X denotes the Frobenius morphism on X and H denotes the a cohomology sheaf of F∗Ω•X . If the variety is not smooth, not much is known about the properties of the Cartier operator and the poor behaviour of the deRham complex in this case makes its study difficult. If one substitutes the deRham complex with the Zariski-deRham complex the situation is better. For e...
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1) The isomorphy type of a finite field K is given by its cardinality |K|, i.e., if K and L are such fields, then K ∼= L iff |K| = |L|. 1) The isomorphy type of an algebraically closed field K is determined by two invariants: (i) Absolute transcendence degree td(K), (ii) The characteristic p = char(K) ≥ 0. In other words, if K and L are algebraically closed fields, then K ∼= L iff td(K) = td(L)...
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ژورنال
عنوان ژورنال: Journal of Pure and Applied Algebra
سال: 1989
ISSN: 0022-4049
DOI: 10.1016/0022-4049(89)90062-5