Description
Remove an inverse-cubic h scale from a supplied volume.
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 an inverse-cubic h scale from a supplied volume.
When to use this tool
Use Comoving Volume H Cubed Unit Pair when you already have volumeInHInverseCubicUnits, hValue and need to remove an inverse-cubic h scale from a supplied volume.
How to use the tool and how it works
- Enter volumeInHInverseCubicUnits, hValue. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read physicalCubicVolume. Use the output convention below.
Require volume>=0 and hValue positive/finite; divide by h three times in succession.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| volumeInHInverseCubicUnits | Volume In HInverse Cubic Units | Required. Finite number; minimum 0. |
| hValue | H Value | Required. Finite number; strictly above 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| physicalCubicVolume | volumeInHInverseCubicUnits/hValue³; removes h scaling only. It remains comoving if the input is comoving, without an a³ proper-volume conversion. | Required. Finite number. |
{
"input": {
"volumeInHInverseCubicUnits": 8,
"hValue": 0.5
},
"output": {
"physicalCubicVolume": 64
}
}Limitations and assumptions
- Output uses the underlying cubic length unit. Removing h^-3 does not itself convert comoving volume to same-epoch proper volume; no a^3 factor or distance integral is added.
- 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
Similar or alternative tools
- Cosmology Distance Physical Comoving Label
Crosswalk supplied same-epoch physical and comoving lengths using a scale factor.
- Cosmological H Scaled Mass Crosswalk
Apply a supplied h exponent to a quoted cosmological mass.