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arXiv · 0909.5092

Reconstruction of the Primordial Power Spectrum by Direct Inversion

Gavin Nicholson·Carlo R. Contaldi·Paniez Paykari
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Abstract

We introduce a new method for reconstructing the primordial power spectrum, $P(k)$, directly from observations of the Cosmic Microwave Background (CMB). We employ Singular Value Decomposition (SVD) to invert the radiation perturbation transfer function. The degeneracy of the multipole $\ell$ to wavenumber $k$ linear mapping is thus reduced. This enables the inversion to be carried out at each point along a Monte Carlo Markov Chain (MCMC) exploration of the combined $P(k)$ and cosmological parameter space. We present best--fit $P(k)$ obtained with this method along with other cosmological parameters.

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Gavin Nicholson, Carlo R. Contaldi, Paniez Paykari. 2009-09-28. Reconstruction of the Primordial Power Spectrum by Direct Inversion. https://doi.org/10.1088/1475-7516/2010/01/016

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