Description
Remove the h factor from a supplied h/Mpc wavenumber.
Cosmological quantities depend on scale factor, redshift, distance definition and the dimensionless Hubble parameter h. Proper and comoving distances differ at a specified epoch, and h-scaled units differ from the dimensional Hubble constant. A scalar rescaling or model contribution preserves supplied conventions without fitting a cosmology or inferring an observed distance.
Remove the h factor from a supplied h/Mpc wavenumber.
When to use this tool
Use Wave Number H Per Mpc Label when you already have quotedWavenumber, h and need to remove the h factor from a supplied h/Mpc wavenumber.
How to use the tool and how it works
- Enter quotedWavenumber, h. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read inverseMegaparsecs, label. Use the output convention below.
Require quotedWavenumber>=0 and h>0; return quotedWavenumber*h in inverse megaparsecs and retain the h/Mpc label.1
The dimensionless Hubble parameter h expresses H0 in units of 100 km/s/Mpc. It is distinct from a dimensional Hubble-constant value.2
| Input field | Meaning and units | Accepted input |
|---|---|---|
| quotedWavenumber | Numeric coefficient of h Mpc^-1; multiply by h for Mpc^-1. | Required. Finite number; minimum 0. |
| h | Positive dimensionless H0/(100 km/s/Mpc); do not enter the dimensional Hubble constant. | Required. Finite number; strictly above 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| inverseMegaparsecs | Inverse Megaparsecs | Required. Finite number. |
| label | Label | Required. Text; maximum UTF-16 length 8192. |
{
"input": {
"quotedWavenumber": 0.2,
"h": 0.7
},
"output": {
"inverseMegaparsecs": 0.13999999999999999,
"label": "0.2 h/Mpc (h=0.7)"
}
}Limitations and assumptions
- h is the dimensionless convention parameter, not H0 with velocity/distance units. No cosmological parameter, distance or physical/comoving scale is estimated.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Use the complete cosmological model and its parameter, epoch and unit definitions for a physical inference. Review redshift, distance, lensing and spectrum conventions before combining these local terms; they do not perform line-of-sight integration, parameter estimation or uncertainty analysis.
References
-
Calculation and input contract: cosmology/wave-number-h-per-mpc-label — tool.io
-
Distance measures in cosmology — David W. Hogg
Similar or alternative tools
- Cosmological H Scaled Mass Crosswalk
Apply a supplied h exponent to a quoted cosmological mass.
- Comoving Volume H Cubed Unit Pair
Remove an inverse-cubic h scale from a supplied volume.