Mathematics – Number Theory
Scientific paper
2006-06-19
Mathematics
Number Theory
43 pages. Changes from previous version: some improvements in section 5, simplification in section 7, cut most of section 9 (w
Scientific paper
Let k be a number field and X a smooth projective k-variety. In this paper, we study the information obtainable from descent via torsors under finite k-group schemes on the location of the k-rational points on X within the adelic points. Our main result is that if a curve C/k maps nontrivially into an abelian variety A/k such that A(k) is finite and Sha(k,A) has no nontrivial divisible elements, then the information coming from finite abelian descent cuts out precisely the rational points of C. We conjecture that this is the case for all curves of genus at least 2. We relate finite descent obstructions to the Brauer-Manin obstruction; in particular, we prove that on curves, the Brauer set equals the set cut out by finite abelian descent. Our conjecture therefore implies that the Brauer-Manin obstruction against rational points in the only one on curves.
No associations
LandOfFree
Finite descent obstructions and rational points on curves does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Finite descent obstructions and rational points on curves, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Finite descent obstructions and rational points on curves will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-304985