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S May 9, 2017 at 15:05 history bounty ended CommunityBot
S May 9, 2017 at 15:05 history notice removed CommunityBot
May 6, 2017 at 20:24 answer added John Wiltshire-Gordon timeline score: 4
S May 1, 2017 at 13:21 history bounty started Saal Hardali
S May 1, 2017 at 13:21 history notice added Saal Hardali Draw attention
S Apr 13, 2017 at 21:56 history bounty ended CommunityBot
S Apr 13, 2017 at 21:56 history notice removed CommunityBot
Apr 6, 2017 at 11:08 comment added Saal Hardali These are sheaves on X equivariant w.r.t. G. so you have extra structure on them.
Apr 6, 2017 at 11:06 comment added Artur Jackson Sorry, my question was unhelpful actually. I left something out: Just to be clear, these are sheaves on the underlying set $X$ of a G-set ($X$,action)? (And not the translation groupoid for example.)
Apr 6, 2017 at 11:02 comment added Saal Hardali I think the question is pretty clear as is. I did right "k-vector spaces". By a G-set I mean nothing more than a set with an action of a group. Indeed in this case sheaves=presheaves. I'd like to know what happens in the reasonably general context though.
Apr 6, 2017 at 0:10 comment added Artur Jackson Maybe you want to be clearer: $Sh_G(X)$ is ``$G$-equivariant sheaves taking values in $\mathbf{Vect}_k$''? You say `sheaves.' So your $X$'s are topological $G$-sets, i.e., $G$-spaces? Or do you just want pre-sheaves = sheaves for the discrete topology? Or you are viewing a $G$-set as a groupoid (category)?
Apr 5, 2017 at 22:46 comment added Marc Hoyois Taking the quotient groupoid is the natural thing to do in any geometric context: sets → groupoids, schemes → algebraic stacks, topological spaces → topological stacks, etc.
Apr 5, 2017 at 20:42 history edited Saal Hardali CC BY-SA 3.0
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Apr 5, 2017 at 20:40 comment added Saal Hardali @MarcHoyois Although I phrased everything in the simple context of sets I'm looking for a natural answer that would generalize easily to any context. Hopefully with some intuitive/geometric/hands-on interpretation of the the functors involved beyond the formal existence argument.
Apr 5, 2017 at 20:23 comment added Marc Hoyois Your $Sh_G(X)$ is just presheaves on the quotient groupoid $X/G$. For any morphism between groupoids you formally get three adjoint functors on presheaves.
S Apr 5, 2017 at 20:15 history bounty started Saal Hardali
S Apr 5, 2017 at 20:15 history notice added Saal Hardali Draw attention
Apr 3, 2017 at 13:35 history asked Saal Hardali CC BY-SA 3.0