Source: https://guthlabs.ai/docs/instruments/relativistic-doppler-effect-calculator/implementation/

instrument implementation / implementation-contract

# Relativistic Doppler Effect Calculator implementation

A source-bound implementation contract for Relativistic Doppler Effect Calculator; deployment and executable qualification remain separate.

Status: **VERIFIED_CLEAN**Lifecycle: **implementation-contract**

## Binding contract

This record describes what an executable surface must bind and validate. It does not claim that a public calculator, package, or production route is deployed.

**Record owner**: Guth Instruments

**Lifecycle**: verified-clean

**Evidence ID**: t5-085

**Effect**: Computation or source lookup only

## Input and validation requirements

The formula encounters a division-by-zero singularity at beta = -1 and should reject that input. The negative-beta plus explicit-direction case also exposes an unresolved signed-beta versus direction-field convention ambiguity.

## Required corrections

No binding erratum is attached to this unique-name record. Implementers must still preserve the declared units, domain, and failure behavior.

## Inspectable interface fixture

The sample below is evidence for interface and validation tests, not a production implementation.

````
{
  "inputs": {
    "source_frequency_hz": 600000000000000,
    "beta": 0.6,
    "direction": "receding",
    "c_m_per_s": 299792458
  },
  "expected_outputs": {
    "observed_frequency_hz": 300000000000000,
    "observed_wavelength_m": 9.993081933333334e-7,
    "redshift_z": 1
  },
  "working": "Doppler factor=sqrt((1-0.6)/(1+0.6))=sqrt(0.4/1.6)=sqrt(0.25)=0.5. f_obs=600000000000000*0.5=300000000000000 Hz. lambda_obs=c/f_obs=299792458/300000000000000=9.993081933333333e-7 m. z=f_src/f_obs-1=600000000000000/300000000000000-1=2-1=1."
}
````

## Other records

[01**Overview**](<https://guthlabs.ai/docs/instruments/relativistic-doppler-effect-calculator/>)[02**Mechanism**](<https://guthlabs.ai/docs/instruments/relativistic-doppler-effect-calculator/mechanism/>)[04**Qualification**](<https://guthlabs.ai/docs/instruments/relativistic-doppler-effect-calculator/qualification/>)

## Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

- `VERIFIED_LEDGER.json`

- `evidence-tranche5/tranche5-results.json`