title: Constraining isocurvature perturbations with cosmic microwave background polarization.
abstract: The role of cosmic microwave background polarization data in constraining the presence of primordial isocurvature modes is examined. While MAP will be unable to simultaneously constrain isocurvature modes and cosmological parameters, PLANCK will set strong limits on isocurvature modes. If one allows isocurvature modes, the recently obtained BOOMERANG measurement of the curvature of the Universe fails. However, a comparably sensitive polarization measurement on the same angular scales will permit a determination of the curvature without the prior assumption of adiabaticity.
authors.affiliation: Department of Applied Mathematics and Theoretical Physics, Centre for Mathematical Sciences, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA, United Kingdom.
authors.forename: M
authors.initials: M
authors.lastname: Bucher
authors.forename: K
authors.initials: K
authors.lastname: Moodley
authors.forename: N
authors.initials: N
authors.lastname: Turok