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arXiv · 1301.4831

Matter bispectrum in cubic Galileon cosmologies

Nicola Bartolo·Emilio Bellini·Daniele Bertacca·Sabino Matarrese
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Abstract

In this paper we obtain the bispectrum of dark matter density perturbations in the frame of covariant cubic Galileon theories. This result is obtained by means of a semi-analytic approach to second-order perturbations in Galileon cosmologies, assuming Gaussian initial conditions. In particular, we show that, even in the presence of large deviations of the linear growth-rate w.r.t. the ΛCDM one, at the bispectrum level such deviations are reduced to a few percent.

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Nicola Bartolo, Emilio Bellini, Daniele Bertacca, Sabino Matarrese. 2013-05-03. Matter bispectrum in cubic Galileon cosmologies. https://doi.org/10.1088/1475-7516%2F2013%2F03%2F034

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