Astronomy and Astrophysics – Astrophysics
Scientific paper
2000-07-24
Phys.Rev. D66 (2002) 023528
Astronomy and Astrophysics
Astrophysics
48 pages, compressed and RevTex file, including three postscript Figures. Note: there are a large number of Tables in this pap
Scientific paper
10.1103/PhysRevD.66.023528
The most general homogeneous and isotropic statistical ensemble of linear scalar perturbations which are regular at early times, in a universe with only photons, baryons, neutrinos, and a cold dark matter (CDM) component, is described by a 5x5 symmetric matrix-valued generalization of the power spectrum. This description is complete if the perturbations are Gaussian, and even in the non-Gaussian case describes all observables quadratic in the small perturbations. The matrix valued power spectrum describes the auto- and cross-correlations of the adiabatic, baryon isocurvature, CDM isocurvature, neutrino density isocurvature, and neutrino velocity isocurvature modes. In this paper we examine the prospects for constraining or discovering isocurvature modes using forthcoming MAP and PLANCK measurements of the cosmic microwave background (CMB) anisotropy. We also consider the degradation in estimates of the cosmological parameters resulting from the inclusion of these modes. In the case of MAP measurements of the temperature alone, the degradation is drastic. When isocurvature modes are admitted, uncertainties in the amplitudes of the mode auto-- and cross--correlations, and in the cosmological parameters, become of order one. With the inclusion of polarisation (at an optimistic sensitivity) the situation improves for the cosmological parameters but the isocurvature modes are still only weakly constrained. Measurements with PLANCK's estimated errors are far more constraining, especially so with the inclusion of polarisation. If PLANCK operates as planned the amplitudes of isocurvature modes will be constrained to less than ten per cent of the adiabatic mode and simultaneously key cosmological parameters will be estimated to a few per cent or better.
Bucher Martin
Moodley Kavilan
Turok Neil
No associations
LandOfFree
Characterising the Primordial Cosmic Perturbations does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Characterising the Primordial Cosmic Perturbations, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Characterising the Primordial Cosmic Perturbations will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-406198