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arXiv · astro-ph/0401417

The initial conditions of the universe: how much isocurvature is allowed?

M. Bucher·J. Dunkley·P. G. Ferreira·K. Moodley·C. Skordis
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Abstract

We investigate the constraints imposed by the current data on correlated mixtures of adiabatic and non-adiabatic primordial perturbations. We discover subtle flat directions in parameter space that tolerate large (~60%) contributions of non-adiabatic fluctuations. In particular, larger values of the baryon density and a spectral tilt are allowed. The cancellations in the degenerate directions are explored and the role of priors elucidated.

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M. Bucher, J. Dunkley, P. G. Ferreira, K. Moodley, C. Skordis. 2004-01-21. The initial conditions of the universe: how much isocurvature is allowed?. https://doi.org/10.1103/physrevlett.93.081301

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