English

Mixed Tate motives and the unit equation II

Number Theory 2020-07-15 v5 Algebraic Geometry

Abstract

Over the past fifteen years or so, Minhyong Kim has developed a framework for making effective use of the fundamental group to bound (or even compute) integral points on hyperbolic curves. This is the third installment in a series whose goal is to realize the potential effectivity of Kim's approach in the case of the thrice punctured line. As envisioned in the last installment, we construct an algorithm whose output upon halting is provably the set of integral points, and whose halting would follow from conjectures. Our results go a long way towards achieving our goals over the rationals, while broaching the topic of higher number fields.

Keywords

Cite

@article{arxiv.1510.01362,
  title  = {Mixed Tate motives and the unit equation II},
  author = {Ishai Dan-Cohen},
  journal= {arXiv preprint arXiv:1510.01362},
  year   = {2020}
}

Comments

The "realization algorithm" of previous versions contained an error, so has been substantially reworked in section 3.7. Numerous inaccuracies in my account of the numerical approximation algorithm have been corrected in section 6. Finally, the Hasse principle in Galois cohomology of Condition 2.2.13 is now shown to follow from a conjecture due to Jannsen. To appear in Algebra and Number Theory