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Leray's theorem (Theorem)

Let $\mathcal F$ be a sheaf on a topological space $X$ and $\mathcal U=\{U_i\}$ an open cover of $X$ If $\mathcal F$ is acyclic on every finite intersection of elements of $\mathcal U$ then $$ \check H^q(\mathcal U,\mathcal F)=\check H^q(X,\mathcal F), $$ where $\check H^q(\mathcal U,\mathcal F)$ is the $q$ th Cech cohomology group of $\mathcal F$ with respect to the open cover $\mathcal U$

Bibliography

1
Bonavero, Laurent. Cohomology of Line Bundles on Toric Varieties, Vanishing Theorems. Lectures 16-17 from ``Summer School 2000: Geometry of Toric Varieties.''




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"Leray's theorem" is owned by mathcam. [ full author list (2) | owner history (1) ]
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See Also: sheaf, sheaf cohomology, sheaf cohomology


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proof of Leray's Theorem (via spectral sequences) (Proof) by mathcam
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Cross-references: open cover, topological space, sheaf

This is version 6 of Leray's theorem, born on 2004-10-09, modified 2005-03-18.
Object id is 6328, canonical name is LeraysTheorem.
Accessed 1634 times total.

Classification:
AMS MSC18G60 (Category theory; homological algebra :: Homological algebra :: Other homology theories)

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