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Timeline for Why no abelian varieties over Z?

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Mar 25, 2015 at 5:03 comment added Filippo Alberto Edoardo @ Emerton: but oddly enough, Khare-Wintenberger need an inductive argument whose basic step relies upon Schoof's work on abelian varieties over number field with few bad places... ;)
Feb 10, 2010 at 6:07 history edited Emerton CC BY-SA 2.5
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Jan 6, 2010 at 11:56 vote accept Ilya Nikokoshev
Jan 6, 2010 at 6:02 comment added Emerton I should also add, regarding my paranthetical remark, that Tate's non-existence result for mod 2 2-dim'l Galois reps. unram. outside 2 is a crucial ingredient in the proof of Serre's conjecture by Khare and Wintenberger, so logically that situation is quite different from the elliptic curve case, where Tate's non-existence result plays no role in the proof of modularity.
Jan 6, 2010 at 5:51 comment added S. Carnahan Oh, that's really good to know. Thanks!
Jan 6, 2010 at 5:17 comment added Emerton I don't think there is any hidden circular reasoning there, and in fact is a perfectly good way to think about it. Actually, Tate's result served as an early consistency check for the modularity conjecture. (Just as his result on the non-existence of continuous representations $\rho:G_{\mathbb Q} \to GL_2(\bar{F}_2)$ unramified outside 2 served as an early consistency check on Serre's conjecture.)
Jan 6, 2010 at 5:13 comment added S. Carnahan One might say that the elliptic curve case follows from nonexistence of weight 2 level 1 cusp forms + modularity, but there may be some hidden circular reasoning (and it seems like a backwards way to look at things).
Jan 6, 2010 at 1:23 comment added Anweshi @Ilya. I took a look at page 16. That is Chapter 2 on Faltings theorem, and I had imagined that it was a separate article. Read on, you will find that Faltings settled that too. The role of Shafarevich is that he proved it for elliptic curves -- the proof is rather easy, it can be found in Silverman's book on elliptic curves. The higher dimensional case was then called "Shafarevich conjecture".
Jan 6, 2010 at 0:23 comment added Emerton From a number theorist's point of view, $p$-adic Hodge theory is one of the key ingredients in the theory of motives, so these arguments are motivic, in a certain sense. (Perhaps one can say that $p$-adic Hodge theory encodes arithmetic properties of motives in a way analogously to the way that Hodge theory encodes geometric and analytic properties.)
Jan 6, 2010 at 0:16 history edited Emerton CC BY-SA 2.5
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Jan 5, 2010 at 23:50 comment added Anweshi Faltings proved that also, along with the Mordell conjecture. See Darmon's article on Faltings' theorem.
Jan 5, 2010 at 23:33 comment added Ilya Nikokoshev Re: generalized by Faltings to abelian varieties. That's one more reason I ask: Darmon seems to call this a Shafarevich Conjecture (page 16) rather then a result.
Jan 5, 2010 at 23:23 history edited Emerton CC BY-SA 2.5
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Jan 5, 2010 at 23:16 history answered Emerton CC BY-SA 2.5