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May 3, 2020 at 9:32 vote accept Christopher D. Long
Dec 3, 2018 at 7:40 answer added François Brunault timeline score: 6
Nov 30, 2018 at 13:35 comment added Chris Wuthrich You are asking if $E(\mathbb{Q})/2E(\mathbb{Q})\to E(\mathbb{R})/2E(\mathbb{R})$ is surjective. Maybe one can say something about the image of the $2$-Selmer group instead; there might be reasons that other local conditions impose the same as the real condition. Instead for the actual rational points, I doubt it is easy to say much.
Nov 30, 2018 at 13:30 comment added Christopher D. Long Yes, thanks, you are correct that it only makes sense to ask if there is a generator on the non-identity component.
Nov 30, 2018 at 13:13 comment added WhatsUp Sorry, now I remember that the result for $N$ odd is that this equation doesn't have solutions in positive integers, which is equivalent to saying that all rational points are located on the identity component.
Nov 30, 2018 at 13:10 comment added WhatsUp Of course, $E(\mathbb{Q})_{tors}$ should a priori be contained in the identity component, for this to make sense.
Nov 30, 2018 at 13:10 comment added François Brunault Did you try to see where the generators are located for, say, the family of all elliptic curves of rank 1, positive discriminant and trivial torsion?
Nov 30, 2018 at 13:02 comment added WhatsUp I think there is a result saying that there is no non-trivial rational point for $N$ odd. Also, I don't understand what you mean by "have 2 on identity", etc. It seems to me that it only makes sense to say whether there is a generator on the non-identity component: if $P, Q$ is a set of generators, then $P, P + Q$ also. This is equivalent to asking whether $E(\mathbb{Q})$ is contained in the identity component.
Nov 30, 2018 at 12:35 history asked Christopher D. Long CC BY-SA 4.0