Description
Apply a supplied cosmological redshift time-dilation factor.
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.
Apply a supplied cosmological redshift time-dilation factor.
When to use this tool
Use Cosmological Time Dilation Interval Pair when you already have restInterval, redshift and need to apply a supplied cosmological redshift time-dilation factor.
How to use the tool and how it works
- Enter restInterval, redshift. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read observedInterval, dilationFactor. Use the output convention below.
Require restInterval>=0 and redshift>-1; return factor=1+z and observedInterval=restInterval*factor.1
Cosmological redshift stretches an emitted time interval by 1+z. Applying that factor does not identify a source redshift or remove other timing effects.2
| Input field | Meaning and units | Accepted input |
|---|---|---|
| restInterval | Nonnegative interval in the desired time unit; observedInterval uses the same unit. | Required. Finite number; minimum 0. |
| redshift | Dimensionless z>-1; dilation factor=1+z. | Required. Finite number; strictly above -1. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| observedInterval | Observed Interval | Required. Finite number. |
| dilationFactor | Dilation Factor | Required. Finite number. |
{
"input": {
"restInterval": 10,
"redshift": 2
},
"output": {
"observedInterval": 30,
"dilationFactor": 3
}
}Limitations and assumptions
- Matching time units and the stated source/observer convention are assumed. No redshift, distance, local clock correction or other source of time dilation is determined.
- 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
- Cosmological Simulation Snapshot Scale Tag
Label a simulation snapshot's supplied scale factor and corresponding redshift.
- Redshift Velocity Small Offset Convention
Calculate a small-redshift-offset velocity approximation under supplied conventions.