Universitat de València

University of Michigan

Professor of Astrophysics, Institute of Theoretical Astrophysics, University of Oslo

Corporate Fellow, Oak Ridge National Laboratory

Professor of Physics, University of Warwick

Texas A&M, Deparment of Mathematics

Professor of Astrophysics, University of Delaware

Professor of Physics and Astronomy, Director Origins Inst., McMaster University

Senior Scientist Emeritus

LPP (Observatoire de Paris-PSL) & RoCS (Universitet i Oslo)