3-nilpotent obstructions to pi_1 sections for P^1_Q - {0,1,infty}

Journal Article

We study which rational points of the Jacobian of P^1_K -{0,1,infty} can be lifted to sections of geometrically 3 nilpotent quotients of etale pi_1 over the absolute Galois group. This is equivalent to evaluating certain triple Massey products of elements of H^1(G_K). For K=Q_p or R, we give a complete mod 2 calculation. This permits some mod 2 calculations for K = Q. These are computations of obstructions of Jordan Ellenberg.

Full Text

Duke Authors

Cited Authors

  • Wickelgren, K

Cited Editors

  • Stix, J

Published Date

  • January 1, 2012

Published In

  • The Arithmetic of Fundamental Groups Pia 2010, Editor J. Stix, Contributions in Mathematical and Computational Sciences, Vol. 2, Springer Verlag Berlin Heidelberg, 2012