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Results tagged with gerbes
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"Gerbe" is a construct in homological algebra and topology. They can be seen as a generalization of principal bundles to the setting of 2-categories. "Gerbe" is a French (and archaic English) word that literally means wheat sheaf. Gerbes were introduced by Jean Giraud (Giraud 1971) following ideas of Alexandre Grothendieck as a tool for non-commutative cohomology in degree 2.
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Why do gerbes live in H^2?
It might be okay for $\mathbb{G}_m$-gerbes, by accident, but for general non-abelian gerbes you will run into trouble. … (It might still be okay for $\mu$-gerbes, where $\mu$ is a sheaf of abelian groups over X). …
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