Cohomology with Proper Supports and Ehresmann’s Theorem
نویسنده
چکیده
2 Cohomology with Proper Supports In our étale cohomology setting, however, j! no longer sends injectives to injectives, and the isomorphism (1.1) may not hold. Consider the following example: Example 2.1. Consider f : AC → C. A closed subset of AC is either the entire line AC or a finite set of closed points, so for any sheaf F on AC, if a section s ∈ Γ(AC,F) has proper support, then supp(s) must be a finite set. Therefore, Γc(A 1 C, •) = ⊕
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تاریخ انتشار 2017