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arXiv · 1709.09135

A comparison of Einstein-Boltzmann solvers for testing General Relativity

E. Bellini·A. Barreira·N. Frusciante·B. Hu·S. Peirone·M. Raveri·M. Zumalacárregui·A. Avilez-Lopez·M. Ballardini·R. A. Battye·B. Bolliet·E. Calabrese·Y. Dirian·P. G. Ferreira·F. Finelli·Z. Huang·M. M. Ivanov·J. Lesgourgues·B. Li·N. A. Lima·F. Pace·D. Paoletti·I. Sawicki·A. Silvestri·C. Skordis·C. Umiltà·F. Vernizzi
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Abstract

We compare Einstein-Boltzmann solvers that include modifications to General Relativity and find that, for a wide range of models and parameters, they agree to a high level of precision. We look at three general purpose codes that primarily model general scalar-tensor theories, three codes that model Jordan-Brans-Dicke (JBD) gravity, a code that models f(R) gravity, a code that models covariant Galileons, a code that models Ho\v{r}ava-Lifschitz gravity and two codes that model non-local models of gravity. Comparing predictions of the angular power spectrum of the cosmic microwave background and the power spectrum of dark matter for a suite of different models, we find agreement at the sub-percent level. This means that this suite of Einstein-Boltzmann solvers is now sufficiently accurate for precision constraints on cosmological and gravitational parameters.

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E. Bellini, A. Barreira, N. Frusciante, B. Hu, S. Peirone, M. Raveri, M. Zumalacárregui, A. Avilez-Lopez, M. Ballardini, R. A. Battye, B. Bolliet, E. Calabrese, Y. Dirian, P. G. Ferreira, F. Finelli, Z. Huang, M. M. Ivanov, J. Lesgourgues, B. Li, N. A. Lima, F. Pace, D. Paoletti, I. Sawicki, A. Silvestri, C. Skordis, C. Umiltà, F. Vernizzi. 2017-09-26. A comparison of Einstein-Boltzmann solvers for testing General Relativity. https://doi.org/10.1103/physrevd.97.023520

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