Talk detail

Participant	Vallejo Peña, Sergio Andrés
Institution	Universidad de Antioquia - Calle 67 No. 53 - 108 - Medellin - Antioquia - Colombia

Session	BS2	Accepted	Yes	Order	10	Time	18:15	15'
Talk	Oral abstract	Title	The effects of anisotropy and non-adiabaticity on the evolution of the curvature perturbation
Coauthors	Sasaki, Misao; Romano, Antonio E.; Naruko, Atsushi;
Abstract	We derive a general equation for the evolution of the curvature perturbation on comoving slices $\mathcal{R}_c$ in the presence of anisotropic and non-adiabatic pressure terms in the energy-momentum tensor of matter field. The equation is obtained by manipulating the perturbed Einstein equations in the comoving slicing. It could be used to study the evolution of perturbations for a system with an anisotropic energy-momentum tensor, such as in the presence of a vector field or in the presence of non-adiabaticity, such as in a multi-field system.
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Session	PT2	Accepted	Yes	Order	2	Time	15:35	20'
Talk	Oral abstract	Title	Reconstructing the metric of the local Universe from number counts observations
Coauthors	Romano, Antonio E.
Abstract	Number counts observations available with new surveys such as the Euclid mission will be an important source of information about the metric of the Universe. We compute the low red-shift expansion for the energy density and the density contrast using an exact spherically symmetric solution in presence of a cosmological constant. At low red-shift the expansion is more precise than linear perturbation theory prediction. We then use the local expansion to reconstruct the monopole component of the metric from the monopole of the density contrast. We test the inversion method using numerical calculations and find a good agreement within the regime of validity of the red-shift expansion. The method could be applied to observational data to reconstruct the metric of the local Universe with a level of precision higher than the one achievable using perturbation theory.
Pdf file