a1 Mathematical Institute, Oxford University, Oxford, UK
a2 Universidad de Los Andes, Departamento de Matemáticas, CRA. 1 No 18A-10, Bogotá, Colombia. E-mail: firstname.lastname@example.org, URL: http://matematicas.uniandes.edu.co/cv/webpage.php?Uid=aonshuus
We study the behaviour of stable types in rosy theories. The main technical result is that a non-þ-forking extension of an unstable type is unstable. We apply this to show that a rosy group with a þ-generic stable type is stable. In the context of super-rosy theories of finite rank we conclude that non-trivial stable types of Uþ-rank 1 must arise from definable stable sets.
(Received October 26 2008)
* Supported by the EPSRC grant no. EP C52800X 1