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Coboundary operators, 1-cocycles and computing cohomology

My question is about the compatibility and consistency between two definitions of cohomology in two books. I asked this question about 10 days ago on MathSE and I set a bounty on it, but I didn't ...
Tireless and hardworking's user avatar
7 votes
4 answers
608 views

Is cohomology of groups all about $H^{i}: -2\leq i\leq 2$?

I am reading Class field theory - Bonn Lectures by Neukirch. Given a $G$ module $A$ he defines Cohomology groups $H^i(G,A) : i\in \mathbb{Z}$ by considering some complete resolution of $G$ modules ...
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74 votes
10 answers
18k views

Intuition for Group Cohomology

I'm beginning to learn cohomology for cyclic groups in preparation for use in the proofs of global class field theory (using ideal-theoretic arguments). I've seen the proof of the long exact sequence ...
David Corwin's user avatar
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