Astronomy and Astrophysics – Astrophysics
Scientific paper
2007-06-14
JCAP 0708:006,2007
Astronomy and Astrophysics
Astrophysics
10 pages, 4 figures. The flow code used in this paper is available at http://www.physics.buffalo.edu/whkinney/flowcode. Refere
Scientific paper
10.1088/1475-7516/2007/08/006
We investigate the ability of current CMB data to reliably constrain the form of the primordial power spectrum generated during inflation. We attempt to identify more exotic power spectra that yield equally good fits to the data as simple power-law spectra. In order to test a wide variety of spectral shapes, we combine the flow formalism, which is a method of stochastic model generation, with a numerical integration of the mode equations of quantum fluctuations. This allows us to handle inflation models that yield spectra that are not well described by the standard spectral parameterization. Using the latest WMAP data-set, we find a high degree of variation in possible spectral shapes. In particular, we find strongly running spectra arising from fast-rolling inflaton fields providing equally good fits to the data as power-law spectra arising from slowly-rolling fields. Current data poorly constrains the spectrum on scales (k < 0.01 h{\rm Mpc}^{-1}), where the error due to cosmic variance is large. Among the statistically degenerate models, we identify spectra with strong running on these larger scales, but with reduced running at smaller scales. These models predict values for the tensor-to-scalar ratio, (r), that lie outside the 2-(\sigma) confidence interval obtained from SDSS+WMAP data for spectra that are parametrized as power-laws or spectra with constant running. By considering more generalized power spectra, we therefore open up regions of parameter space excluded for simpler models.
Kinney William H.
Powell Brian A.
No associations
LandOfFree
Limits on primordial power spectrum resolution: An inflationary flow analysis 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 Limits on primordial power spectrum resolution: An inflationary flow analysis, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Limits on primordial power spectrum resolution: An inflationary flow analysis will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-330202