pyccl.modified_gravity.mu_Sigma module
- class pyccl.modified_gravity.mu_Sigma.MuSigmaMG(parametrization: str = 'mu_Sigma', mu_0: float = 0, sigma_0: float = 0, c1_mg: float = 1, c2_mg: float = 1, lambda_mg: float = 0)[source]
Bases:
ModifiedGravityThe \(\mu\)-\(\Sigma\) parametrization of modified gravity.
- Parameters:
mu_0 (
float) – One of the parameters of the \(\mu\)-\(\Sigma\) modified gravity model. Defaults to 0.0sigma_0 (
float) – One of the parameters of the \(\mu\)-\(\Sigma\) modified gravity model. Defaults to 0.0c1_mg (
float) – MG parameter that enters in the scale dependence of \(\mu\), affecting its large scale behavior. Default to 1. See, e.g., Eqs. (46) in Ade et al. 2015, where their \(f_1\) and \(f_2\) functions are set equal to the commonly used ratio of dark energy density parameter at scale factor a over the dark energy density parameter todayc2_mg (
float) –MG parameter that enters in the scale dependence of \(\Sigma\) affecting its large scale behavior. Default 1. See, e.g., Eqs. (47) in Ade et al. 2015, where their \(f_1\) and \(f_2\) functions are set equal to the commonly used ratio of dark energy density parameter at scale factor a over the dark energy density parameter today
lambda_mg (
float) –MG parameter that sets the start of dependence on \(c_1\) and \(c_2\) MG parameters. Defaults to 0.0 See, e.g., Eqs. (46) & (47) in Ade et al. 2015, where their \(f_1\) and \(f_2\) functions are set equal to the commonly used ratio of dark energy density parameter at scale factor a over the dark energy density parameter today