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Dec 19, 2022 at 8:34 vote accept Saal Hardali
Dec 19, 2022 at 17:50
Dec 15, 2017 at 13:17 history bumped CommunityBot This question has answers that may be good or bad; the system has marked it active so that they can be reviewed.
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Nov 16, 2017 at 19:10 comment added Jeremy Rickard Also, you seem to suggest that knowing the $\otimes$-structure implies knowing the $\text{Pic}(X)$-action. Is this clear? It would be if the $\otimes$-structure determined the line bundles, rather than just their shifts.
Nov 16, 2017 at 19:07 comment added Jeremy Rickard For any line bundle $\mathcal{L}$, the functor $-\otimes\mathcal{L}$ is a self-equivalence of the derived category that commutes with the action of $\text{Pic}(X)$, so I don't think you can distinguish different line bundles without using the $\otimes$-structure, or only using the $\text{Pic}(X)$-action.
Nov 15, 2017 at 12:23 history edited Saal Hardali CC BY-SA 3.0
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S Nov 15, 2017 at 12:20 history bounty started Saal Hardali
S Nov 15, 2017 at 12:20 history notice added Saal Hardali Draw attention
Nov 13, 2017 at 8:01 history edited Saal Hardali CC BY-SA 3.0
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Nov 13, 2017 at 7:59 comment added Saal Hardali @YosemiteSam Edited so that the question would still be interesting despite Tannakian wizardry.
Nov 13, 2017 at 7:57 comment added Saal Hardali @მამუკაჯიბლაძე Of course I agree, still the fact that these two classical definitions agree has always been a miracle for me. I can't think of a proof which doesn't reduce to some form of computation (e.g. serre vanishing).
Nov 13, 2017 at 7:55 history edited Saal Hardali CC BY-SA 3.0
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Nov 13, 2017 at 7:45 history edited Saal Hardali CC BY-SA 3.0
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Nov 13, 2017 at 5:32 comment added მამუკა ჯიბლაძე Well I would say "mysterious" depends on point of view. From another (maybe old-fashioned) point of view, describing all possible maps to the projective space is what the line bundles are for.
Nov 13, 2017 at 3:06 comment added Yosemite Sam he means DQCoh(X), or maybe some infinity version of that. The question can be answered by cheating, as the tensor structure allows you to recover X itself (and therefore any ample line bundle on it). But I don't know how to define ampleness intrinsically.
Nov 13, 2017 at 1:00 comment added R. van Dobben de Bruyn Usually, $\operatorname{QCoh}(X)$ refers to the category of quasi-coherent sheaves on $X$, not its associated derived category. Which of the two are you interested in?
Nov 12, 2017 at 22:59 answer added Leo Alonso timeline score: 5
Nov 12, 2017 at 22:49 history asked Saal Hardali CC BY-SA 3.0