English

Quaternion algebras with the same subfields

Rings and Algebras 2010-12-15 v1

Abstract

G. Prasad and A. Rapinchuk asked if two quaternion division F -algebras that have the same subfields are necessarily isomorphic. The answer is known to be "no" for some very large fields. We prove that the answer is "yes" if F is an extension of a global field K so that F /K is unirational and has zero unramified Brauer group. We also prove a similar result for Pfister forms and give an application to tractable fields.

Keywords

Cite

@article{arxiv.0906.5137,
  title  = {Quaternion algebras with the same subfields},
  author = {Skip Garibaldi and David J. Saltman},
  journal= {arXiv preprint arXiv:0906.5137},
  year   = {2010}
}
R2 v1 2026-06-21T13:18:40.527Z