Cosmology

Cosmology library for Julia


Keywords
astronomy, astrophysics, cosmology, julia
License
MIT

Documentation

Cosmology calculator for Julia

Build Status Coverage Status

Installation

To install the package:

julia> Pkg.add("Cosmology")

Then, to load into your session:

julia> using Cosmology

Cosmological Models

First, pick a cosmological model using the cosmology function, which takes the following options:

h = 0.69 Dimensionless Hubble constant
OmegaK = 0 Curvature density, Ωk
OmegaM = 0.29 Matter density, Ωm
OmegaR = Ωγ + Ων Radiation density, Ωr
Tcmb = 2.7255 CMB temperature (K), used to compute Ωγ
Neff = 3.04 Effective number of massless neutrino species, used to compute Ων
w0 = -1 CPL dark energy equation of state, w = w0 + wa*(1-a)
wa = 0 CPL dark energy equation of state, w = w0 + wa*(1-a)
julia> using Cosmology

julia> c = cosmology()
FlatLCDM(0.69,0.7099122024007928,0.29,8.779759920715362e-5)

julia> c = cosmology(OmegaK=0.1)
OpenLCDM(0.69,0.1,0.6099122024007929,0.29,8.779759920715362e-5)

julia> c = cosmology(w0=-0.9, OmegaK=-0.1)
ClosedWCDM(0.69,-0.1,0.8099122024007929,0.29,8.779759920715362e-5,-0.9,0.0)

Distances

angular_diameter_dist_mpc(cosmo, z) Ratio of an object's proper transverse size (in Mpc) to its angular size (in radians)
comoving_radial_dist_mpc(cosmo, z) Comoving radial distance to redshift z, in Mpc
comoving_volume_gpc3(cosmo, z) Comoving volume out to redshift z, in Gpc3
luminosity_dist_mpc(cosmo, z) Bolometric luminosity distance, in Mpc
distmod(cosmo, z) Distance modulus, in units of magnitude
julia> using Cosmology

julia> c = cosmology(OmegaM=0.26)
FlatLCDM(0.69,0.7399122024007928,0.26,8.779759920715362e-5)

julia> angular_diameter_dist_mpc(c, 1.2)
1784.0089227105118

Times

age_gyr(cosmo, z) Age of the universe at redshift z, in Gyr
lookback_time_gyr(cosmo, z) Difference between age at redshift 0 and age at redshift z, in Gyr
julia> using Cosmology

julia> c = cosmology(OmegaM=0.26)
FlatLCDM(0.69,0.7399122024007928,0.26,8.779759920715362e-5)

julia> age_gyr(c, 1.2)
5.445600787626434