A note on integral points on elliptic curves

Mark Watkins[1]

  • [1] Department of Mathematics University Walk University of Bristol Bristol, BS8 1TW England

Journal de Théorie des Nombres de Bordeaux (2006)

  • Volume: 18, Issue: 3, page 707-720
  • ISSN: 1246-7405

Abstract

top
We investigate a problem considered by Zagier and Elkies, of finding large integral points on elliptic curves. By writing down a generic polynomial solution and equating coefficients, we are led to suspect four extremal cases that still might have nondegenerate solutions. Each of these cases gives rise to a polynomial system of equations, the first being solved by Elkies in 1988 using the resultant methods of Macsyma, with there being a unique rational nondegenerate solution. For the second case we found that resultants and/or Gröbner bases were not very efficacious. Instead, at the suggestion of Elkies, we used multidimensional p -adic Newton iteration, and were able to find a nondegenerate solution, albeit over a quartic number field. Due to our methodology, we do not have much hope of proving that there are no other solutions. For the third case we found a solution in a nonic number field, but we were unable to make much progress with the fourth case. We make a few concluding comments and include an appendix from Elkies regarding his calculations and correspondence with Zagier.

How to cite

top

Watkins, Mark. "A note on integral points on elliptic curves." Journal de Théorie des Nombres de Bordeaux 18.3 (2006): 707-720. <http://eudml.org/doc/249658>.

@article{Watkins2006,
abstract = {We investigate a problem considered by Zagier and Elkies, of finding large integral points on elliptic curves. By writing down a generic polynomial solution and equating coefficients, we are led to suspect four extremal cases that still might have nondegenerate solutions. Each of these cases gives rise to a polynomial system of equations, the first being solved by Elkies in 1988 using the resultant methods of Macsyma, with there being a unique rational nondegenerate solution. For the second case we found that resultants and/or Gröbner bases were not very efficacious. Instead, at the suggestion of Elkies, we used multidimensional $p$-adic Newton iteration, and were able to find a nondegenerate solution, albeit over a quartic number field. Due to our methodology, we do not have much hope of proving that there are no other solutions. For the third case we found a solution in a nonic number field, but we were unable to make much progress with the fourth case. We make a few concluding comments and include an appendix from Elkies regarding his calculations and correspondence with Zagier.},
affiliation = {Department of Mathematics University Walk University of Bristol Bristol, BS8 1TW England},
author = {Watkins, Mark},
journal = {Journal de Théorie des Nombres de Bordeaux},
keywords = {elliptic curves; integral points},
language = {eng},
number = {3},
pages = {707-720},
publisher = {Université Bordeaux 1},
title = {A note on integral points on elliptic curves},
url = {http://eudml.org/doc/249658},
volume = {18},
year = {2006},
}

TY - JOUR
AU - Watkins, Mark
TI - A note on integral points on elliptic curves
JO - Journal de Théorie des Nombres de Bordeaux
PY - 2006
PB - Université Bordeaux 1
VL - 18
IS - 3
SP - 707
EP - 720
AB - We investigate a problem considered by Zagier and Elkies, of finding large integral points on elliptic curves. By writing down a generic polynomial solution and equating coefficients, we are led to suspect four extremal cases that still might have nondegenerate solutions. Each of these cases gives rise to a polynomial system of equations, the first being solved by Elkies in 1988 using the resultant methods of Macsyma, with there being a unique rational nondegenerate solution. For the second case we found that resultants and/or Gröbner bases were not very efficacious. Instead, at the suggestion of Elkies, we used multidimensional $p$-adic Newton iteration, and were able to find a nondegenerate solution, albeit over a quartic number field. Due to our methodology, we do not have much hope of proving that there are no other solutions. For the third case we found a solution in a nonic number field, but we were unable to make much progress with the fourth case. We make a few concluding comments and include an appendix from Elkies regarding his calculations and correspondence with Zagier.
LA - eng
KW - elliptic curves; integral points
UR - http://eudml.org/doc/249658
ER -

References

top
  1. W. Bosma, J. Cannon, C. Playoust, The Magma algebra system. I. The user language. In Computational algebra and number theory Proceedings of the 1st MAGMA Conference held at Queen Mary and Westfield College, London, August 23–27, 1993. Edited by J. Cannon and D. Holt, Elsevier Science B.V., Amsterdam (1997), 235–265. Cross-referenced as J. Symbolic Comput. 24 (1997), no. 3-4, 235–265. Online at http://magma.maths.usyd.edu.au Zbl0898.68039MR1484478
  2. R. P. Brent, Algorithms for Minimization Without Derivatives. Prentice-Hall, Englewood Cliffs, NJ, 1973. Zbl0245.65032MR339493
  3. C. G. Broyden, A Class of Methods for Solving Nonlinear Simultaneous Equations. Math. Comp. 19 (1965), 577–593. Zbl0131.13905MR198670
  4. H. Cohen, A course in computational algebraic number theory. Graduate Texts in Mathematics, 138. Springer-Verlag, New York, 1993. Zbl0786.11071MR1228206
  5. N. D. Elkies, Shimura curves for level-3 subgroups of the (2,3,7) triangle group, and some other examples. To appear in ANTS-VII proceedings, online at http://arxiv.org/math.NT/0409020 Zbl1143.11328MR2282932
  6. N. D. Elkies, M. Watkins, Polynomial and Fermat-Pell families that attain the Davenport-Mason bound. In progress. 
  7. M. J. GreenbergLectures on forms in many variables. W. A. Benjamin, Inc., New York-Amsterdam, 1969. Zbl0185.08304MR241358
  8. M. Hall Jr., The Diophantine equation x 3 - y 2 = k . In Computers in number theory, Proceedings of the Science Research Council Atlas Symposium No. 2 held at Oxford, from 18–23 August 1969. Edited by A. O. L. Atkin and B. J. Birch. Academic Press, London-New York (1971), 173–198. Zbl0225.10012MR323705
  9. S. Lang, Conjectured Diophantine estimates on elliptic curves. In Arithmetic and geometry. Vol. I., edited by M. Artin and J. Tate, Progr. Math., 35, Birkhäuser Boston, Boston, MA (1983), 155–171. Zbl0529.14017MR717593
  10. Macsyma, a sophisticated computer algebra system. See http://maxima.sourceforge.net for history and current version of its descendants. 
  11. PARI/GP, CVS development version 2.2.11, Université Bordeaux I, Bordeaux, France, June 2005. Online at http://pari.math.u-bordeaux.fr 
  12. P. Vojta, Diophantine approximations and value distribution theory. Lecture Notes in Mathematics, 1239. Springer-Verlag, Berlin, 1987. x+132 pp. Zbl0609.14011MR883451
  13. D. Zagier, Large Integral Points on Elliptic Curves, and addendum. Math. Comp. 48 (1987), no. 177, 425–436, 51 (1988), no. 183, 375. Zbl0611.10008MR866125

NotesEmbed ?

top

You must be logged in to post comments.

To embed these notes on your page include the following JavaScript code on your page where you want the notes to appear.

Only the controls for the widget will be shown in your chosen language. Notes will be shown in their authored language.

Tells the widget how many notes to show per page. You can cycle through additional notes using the next and previous controls.

    
                

Note: Best practice suggests putting the JavaScript code just before the closing </body> tag.