학술논문

New MGCAMB tests of gravity with CosmoMC and Cobaya
Document Type
Working Paper
Source
JCAP08(2023)038
Subject
Astrophysics - Cosmology and Nongalactic Astrophysics
Astrophysics - Instrumentation and Methods for Astrophysics
General Relativity and Quantum Cosmology
Language
Abstract
We present a new version of MGCAMB, a patch for the Einstein-Boltzmann solver CAMB for cosmological tests of gravity. New features include a new cubic-spline parameterization allowing for a simultaneous reconstruction of $\mu$, $\Sigma$ and the dark energy density fraction $\Omega_X$ as functions of redshift, the option to work with a direct implementation of $\mu$, $\Sigma$ (instead of converting to $\mu$, $\gamma$ first), along with the option to test models with a scalar field coupled only to dark matter, and the option to include dark energy perturbations when working with $w\ne -1$ backgrounds, to restore consistency with CAMB in the GR limit. This version of MGCAMB comes with a Python wrapper to run it directly from the Python interface, an implementation in the latest version of CosmoMC, and can be used with Cobaya.
Comment: 8 pages + 2 appendices, 4 figures, matches the version accepted to JCAP; MGCAMB, MGCosmoMC and MGCobaya available at https://github.com/sfu-cosmo/MGCAMB, https://github.com/sfu-cosmo/MGCosmoMC, https://github.com/sfu-cosmo/MGCobaya