Cosmology seminar: Iain Alastair Brown: Non-Adiabaticity from Adiabaticity

Iain Alastair Brown is a postdoc with Frode

Abstract: Non-adiabaticity is a generic feature of systems with multiple
fluids, even when the system is started with adiabatic initial conditions.
Any system where fluid densities evolve at a different rate will rapidly
produce non-adiabaticities between the various fluids. This is as true in
cosmology as anywhere, although the issue is typically neglected. I will
examine the effective pressure that arises from non-adiabaticities in the
universe in detail and evaluate its power spectrum. While the non-adiabatic
pressure does not impact on the *linear* cosmic microwave background, the
implications at second-order will be profound, and I will briefly discuss
the impact it will have on vorticity.

Published Feb. 14, 2012 10:54 AM - Last modified June 5, 2012 3:02 PM