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Flat Lambda CDM

flat_lambda_cdm

Functions to compute cosmological quantities under flat lambda CDM model.

Functions

compute_normalized_hubble_parameter

compute_normalized_hubble_parameter(redshift: Array, omega_m: Array) -> Array

Compute the normalized Hubble parameter.

Parameters:

Name Type Description Default
redshift Array

Redshift.

required
omega_m Array

Matter density.

required

Returns:

Type Description
Array

Normalized Hubble parameter.

compute_hubble_parameter

compute_hubble_parameter(redshift: Array, hubble_constant: Array, omega_m: Array) -> Array

Compute the Hubble parameter.

Parameters:

Name Type Description Default
redshift Array

Redshift.

required
hubble_constant Array

Hubble constant in km / s / Mpc.

required
omega_m Array

Matter density.

required

Returns:

Type Description
Array

Hubble parameter in km / s/ Mpc.

compute_comoving_distance

compute_comoving_distance(redshift: Array, hubble_constant: Array, omega_m: Array, n_grid: int = 1000) -> Array

Compute the comoving distance.

Parameters:

Name Type Description Default
redshift Array

Redshift to evaluate the comoving distance.

required
hubble_constant Array

Hubble constant in km / s / Mpc.

required
omega_m Array

Matter density.

required
n_grid int

Number of grid points to perform the numerical integration.

1000

Returns:

Type Description
Array

Comoving distance in Mpc.

compute_differential_comoving_volume

compute_differential_comoving_volume(redshift: Array, hubble_constant: Array, omega_m: Array, n_grid: int = 1000) -> Array

Compute the differential comoving volume.

Parameters:

Name Type Description Default
redshift Array

Redshift.

required
hubble_constant Array

Hubble constant in km / s / Mpc.

required
omega_m Array

Matter density.

required
n_grid int

Number of grid points to perform the numerical integration.

1000

Returns:

Type Description
Array

Differential comoving volume in Mpc^{3}.

compute_luminosity_distance

compute_luminosity_distance(redshift: Array, hubble_constant: Array, omega_m: Array, n_grid: int = 1000) -> Array

Compute the luminosity distance.

Parameters:

Name Type Description Default
redshift Array

Redshift to evaluate the luminosity distance.

required
hubble_constant Array

Hubble constant in km / s / Mpc.

required
omega_m Array

Matter density.

required
n_grid int

Number of grid points to perform the numerical integration.

1000

Returns:

Type Description
Array

Luminosity distance in Mpc.

build_distance_lookup

build_distance_lookup(*, hubble_constant: float = PLANCK18_H0_KM_S_MPC, omega_m: float = PLANCK18_OMEGA_M, max_redshift: float = DEFAULT_MAX_REDSHIFT, n_grid: int = DEFAULT_LOOKUP_GRID_SIZE) -> tuple[Array, Array, Array]

Build flat-ΛCDM lookup tables for redshift, comoving distance, and luminosity distance.

Parameters:

Name Type Description Default
hubble_constant float

Hubble constant in km / s / Mpc.

PLANCK18_H0_KM_S_MPC
omega_m float

Matter density.

PLANCK18_OMEGA_M
max_redshift float

Largest redshift tabulated by the lookup.

DEFAULT_MAX_REDSHIFT
n_grid int

Number of tabulation points.

DEFAULT_LOOKUP_GRID_SIZE

Returns:

Type Description
tuple[Array, Array, Array]

Tuple (redshift_grid, comoving_distance_grid, luminosity_distance_grid).

compute_redshift_from_luminosity_distance

compute_redshift_from_luminosity_distance(luminosity_distance: Array, *, hubble_constant: float = PLANCK18_H0_KM_S_MPC, omega_m: float = PLANCK18_OMEGA_M, max_redshift: float = DEFAULT_MAX_REDSHIFT, n_grid: int = DEFAULT_LOOKUP_GRID_SIZE) -> Array

Invert a luminosity distance to redshift via a flat-ΛCDM lookup table.

Parameters:

Name Type Description Default
luminosity_distance Array

Luminosity distance in Mpc.

required
hubble_constant float

Hubble constant in km / s / Mpc.

PLANCK18_H0_KM_S_MPC
omega_m float

Matter density.

PLANCK18_OMEGA_M
max_redshift float

Largest redshift tabulated by the lookup.

DEFAULT_MAX_REDSHIFT
n_grid int

Number of tabulation points.

DEFAULT_LOOKUP_GRID_SIZE

Returns:

Type Description
Array

Redshift inferred from luminosity_distance.