#10973: Integral points on elliptic curves over number fields
-------------------------------------+-------------------------------------
       Reporter:  justin             |        Owner:  cremona
           Type:  enhancement        |       Status:  needs_work
       Priority:  major              |    Milestone:  sage-6.1
      Component:  elliptic curves    |   Resolution:
       Keywords:  sd32               |    Merged in:
        Authors:  Justin Walker,     |    Reviewers:
  Aly Deines, Jennifer Balakrishnan  |  Work issues:
Report Upstream:  N/A                |       Commit:
         Branch:                     |  7f5036284d4b31fb81bd69a9bf0a1927c70f3206
  u/cremona/trac10973intpts          |     Stopgaps:
   Dependencies:                     |
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Comment (by cremona):

 Replying to [comment:50 chapoton]:
 > Why is this "needs works" ?

 Because I am actively working on it!  Seriously, comparing in detail
 Smart's paper and book and Nook's account in his thesis, I have found two
 things: (1) Smart does not deal properly with torsion generators, Nook
 does and that is in this code but I think I might be able to do better;
 (2) more seriously, Smart derived an upper bound for {{{|x(P)^2\psi(P)|}}}
 (relative to each embedding) which only valid for points with {{{|x(P)|}}}
 bounded below by some quantity (in the appropriate embedding), and this
 means that there are points, possible integral, which fail this condition
 and need to be considered separately.  Over Q that is easily done by
 searching on a finite x-interval, but over a general number field it is
 not clear to me that the "missing" points are in a finite region.
 However,  I am working on a bound (which certainly exists) for
 {{{|x(P)^2\psi(P)|}}} valid for all complex points with any embedding, and
 when that is done I will be changing some of the constants in the code.

 I am not expecting the output to be different in any of the examples (but
 who knows), but I cannot let this in when I have identified but not yet
 fixed this mathematical bug!

--
Ticket URL: <http://trac.sagemath.org/ticket/10973#comment:51>
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