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Oct
7
awarded  Yearling
Jul
2
awarded  Curious
Jun
21
revised Finiteness for separated residually finite modules
deleted 276 characters in body
Jun
21
asked Finiteness for separated residually finite modules
Dec
23
comment Fiber functors to derived categories
Is it really true that $G$ linearly reductive implies $\delta=0$? For example, consider a cts homomorphism $\Gamma\rightarrow G(k)$ where $\Gamma$ is a procyclic group ($k$ could be discrete or have an interesting topology). Then the functor $V\mapsto V^\Gamma$ may not be exact, but the group cohomology $H^i(\Gamma,V)$ is likely computed by the complex $V\rightarrow V$, where the map is $\gamma-1$ for a topological generator $\gamma$ of $\Gamma$. If $V\mapsto V^\Gamma$ is exact, it looks to me like I get 2 $G$-torsors (one for $H^0$, one for $H^1$), but if not, I don't think $\delta=0$.
Dec
22
awarded  Nice Question
Oct
7
awarded  Yearling
Jun
25
awarded  Citizen Patrol
Jan
15
answered the dual abelian scheme
Oct
7
awarded  Yearling
Oct
4
awarded  Nice Question
Sep
30
accepted Are D_dR and D_st “potentially comparable”?
Sep
30
comment Are D_dR and D_st “potentially comparable”?
Great, thanks!
Sep
29
asked Are D_dR and D_st “potentially comparable”?
Jul
3
awarded  Enlightened
Jul
3
awarded  Nice Answer
Jul
2
comment Some help in digesting a paragraph in the introduction of Deligne/Rapoport's “Les Schemas de Modules de Courbes Elliptique”
Yes, we're thinking of $(\mathbf{Z}/n\mathbf{Z})^2$ as a group scheme. Over any base scheme $S$, the scheme structure on $(\mathbf{Z}/n\mathbf{Z})_S^2$ is just $n^2$ disjoint copies of $S$.
Jul
2
awarded  Enlightened
Jul
2
awarded  Nice Answer
Jul
2
answered Some help in digesting a paragraph in the introduction of Deligne/Rapoport's “Les Schemas de Modules de Courbes Elliptique”