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arXiv · 1605.00714

Non-linear structure formation in the "Running FLRW" cosmological model

Antonio Bibiano·Darren J. Croton
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Abstract

We present a suite of cosmological N-body simulations describing the "Running Friedmann-Lema{ï}tre-Robertson-Walker" (R-FLRW) cosmological model. This model is based on quantum field theory in a curved space-time and extends ΛCDM with a time-evolving vacuum density, Λ(z), and time-evolving gravitational Newton's coupling, G(z). In this paper we review the model and introduce the necessary analytical treatment needed to adapt a reference N-body code. Our resulting simulations represent the first realisation of the full growth history of structure in the R-FLRW cosmology into the non-linear regime, and our normalisation choice makes them fully consistent with the latest cosmic microwave background data. The post-processing data products also allow, for the first time, an analysis of the properties of the halo and sub-halo populations. We explore the degeneracies of many statistical observables and discuss the steps needed to break them. Furthermore, we provide a quantitative description of the deviations of R-FLRW from ΛCDM, which could be readily exploited by future cosmological observations to test and further constrain the model.

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Antonio Bibiano, Darren J. Croton. 2016-05-03. Non-linear structure formation in the "Running FLRW" cosmological model. https://doi.org/10.1093/mnras%2Fstw1047

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