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Oct 7, 2019 at 2:56 comment added FunctionOfX yeah... i dont understand it, but it is a result we can quote. I only found it out a few days ago. Thank you so much for your answer.
Oct 7, 2019 at 2:48 comment added Avi Steiner @FunctionOfX ah. That paper. I have it on my list of to-reads for if I ever learn DAG
Oct 7, 2019 at 2:29 comment added FunctionOfX @ avi steiner, thank you. Yeah, the crossed out part was exactly my confusion. D Gaitsgory actually proved this in this paper CRYSTALS AND D-MODULES (prop 4.7.3). The paper uses crystals (which i am not very familiar with), but the proof itself actually doesn't deal with it too much (even though I don't claim I understand it fully).
Oct 6, 2019 at 20:25 comment added Avi Steiner @FunctionOfX So, I was apparently thinking in the crossed-out part that $\Gamma_X$ fixes $\mathcal{D}_V$-injectives, or maybe that one can always resolve by $\mathcal{D}_V$-injectives for which this is true. However, I have no reason to believe either of those statements, hence the crossed-out things. Anyway, I hopefully salvaged things correctly in my latest edit. Let me know!
Oct 6, 2019 at 20:22 history edited Avi Steiner CC BY-SA 4.0
Removed the incorrect part of my first edit, then corrected it.
Oct 4, 2019 at 5:04 comment added FunctionOfX thanks! I still don't quite see how preserve injectives (not necessarily exact) help with computing hom sets, if will be great if you can spell out the detail!
Oct 3, 2019 at 18:16 comment added Avi Steiner @FunctionOfX $\Gamma_X(\mathcal{M})$ is a $\mathcal{D}_V$-submodule of $\mathcal{M}$. One way to see this (at least in the algebraic category, where I feel much more confident about all this stuff) is that $\Gamma_X(\mathcal{M})$ is the sheaf of sections of $\mathcal{M}$ killed by a power of the defining ideal of $X$; now use that this property is preserved under multiplication by elements of $\mathcal{D}_V$.
Oct 3, 2019 at 1:21 comment added FunctionOfX @ Avi Steiner sorry to bother you again, how does D act on $\Gamma_X$
Aug 31, 2019 at 0:18 comment added Avi Steiner @FunctionOfX since $\Gamma_X$ preserves injectives, I can always resolve an object of $\mathcal C$ by injectives in $\mathcal D_V$-mod
Aug 31, 2019 at 0:16 comment added FunctionOfX sorry one last question... surely we need preservation of injective resolutions rather than just injectives...
Aug 30, 2019 at 20:06 comment added Avi Steiner @FunctionOfX ugh! You’re totally right!
Aug 30, 2019 at 20:06 history edited Avi Steiner CC BY-SA 4.0
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Aug 30, 2019 at 20:03 comment added FunctionOfX no problem, in fact thank you so much for your answer, one last question, should the word left adjoint be replaced by right adjoint? I believe it is the right adjoint for closed embedding at least in the smooth case.
Aug 30, 2019 at 19:56 comment added Avi Steiner @FunctionOfX sorry again. I meant fully faithful.
Aug 30, 2019 at 19:55 history edited Avi Steiner CC BY-SA 4.0
edited body
Aug 30, 2019 at 19:55 comment added FunctionOfX and do you mean right adjoint and exact rather than equivalence?
Aug 30, 2019 at 16:00 comment added Avi Steiner @FunctionOfX shoot! Yes, I do! Good catch. It’s fixed now.
Aug 30, 2019 at 15:59 history edited Avi Steiner CC BY-SA 4.0
edited body
Aug 30, 2019 at 13:26 comment added FunctionOfX oh you mean D_V?
Aug 30, 2019 at 1:59 comment added FunctionOfX Sorry, I am not understanding why $\Gamma_X: \mathcal{D}_X$-mod$\to \mathcal{C}$ preserve injectives. In fact, what is $\mathcal{D}_X$
Aug 28, 2019 at 19:43 comment added Avi Steiner @FunctionOfX see my edit
Aug 28, 2019 at 19:43 history edited Avi Steiner CC BY-SA 4.0
added 298 characters in body
Aug 27, 2019 at 1:26 comment added FunctionOfX how do you show fully faithfulness? is that automatic?
Aug 23, 2019 at 23:08 history answered Avi Steiner CC BY-SA 4.0