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Jason R
Jason R
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Derivations for the relativistic Doppler effect abound, which extends the description of the Doppler effect to include the effects of relativity in cases where the source or observer is moving at relativistic velocities. This is all pretty well-described in many sources that I have found.

But what if I would like to include the effects of general relativity instead? Assume the following scenario:

  • There is a stationary source on the earth emitting light at frequency $f$ (with that frequency measured on the reference frame of the source).
  • I launch a rocket that travels to orbit with some velocity profile $\mathbf{v}(t)$.
  • The rocket has a detector that continually observes the light source during its flight.
  • I would like to know the observed frequency of the light wave from the perspective of the rocket, as a function of time, $f'(t')$ (where $t'$ represents time in the rocket's reference frame).

I see three separate effects that would alter the observed frequency aboard the rocket:

  • The classical Doppler effect
  • Time dilation on the rocket due to special relativity
  • Time dilation on the rocket due to general relativity

All of these will change as a function of time as the rocket accelerates and as it moves within Earth's gravitational field. However, all analyses of the relativistic Doppler effect that I've seen only encompass the first two effects. Is there some model that includes all three?

Derivations for the relativistic Doppler effect abound, which extends the description of the Doppler effect to include the effects of relativity in cases where the source or observer is moving at relativistic velocities. This is all pretty well-described in many sources that I have found.

But what if I would like to include the effects of general relativity instead? Assume the following scenario:

  • There is a stationary source on the earth emitting light at frequency $f$.
  • I launch a rocket that travels to orbit with some velocity profile $\mathbf{v}(t)$.
  • The rocket has a detector that continually observes the light source during its flight.
  • I would like to know the observed frequency of the light wave from the perspective of the rocket, as a function of time, $f'(t')$ (where $t'$ represents time in the rocket's reference frame).

I see three separate effects that would alter the observed frequency aboard the rocket:

  • The classical Doppler effect
  • Time dilation on the rocket due to special relativity
  • Time dilation on the rocket due to general relativity

All of these will change as a function of time as the rocket accelerates and as it moves within Earth's gravitational field. However, all analyses of the relativistic Doppler effect that I've seen only encompass the first two effects. Is there some model that includes all three?

Derivations for the relativistic Doppler effect abound, which extends the description of the Doppler effect to include the effects of relativity in cases where the source or observer is moving at relativistic velocities. This is all pretty well-described in many sources that I have found.

But what if I would like to include the effects of general relativity instead? Assume the following scenario:

  • There is a stationary source on the earth emitting light at frequency $f$ (with that frequency measured on the reference frame of the source).
  • I launch a rocket that travels to orbit with some velocity profile $\mathbf{v}(t)$.
  • The rocket has a detector that continually observes the light source during its flight.
  • I would like to know the observed frequency of the light wave from the perspective of the rocket, as a function of time, $f'(t')$ (where $t'$ represents time in the rocket's reference frame).

I see three separate effects that would alter the observed frequency aboard the rocket:

  • The classical Doppler effect
  • Time dilation on the rocket due to special relativity
  • Time dilation on the rocket due to general relativity

All of these will change as a function of time as the rocket accelerates and as it moves within Earth's gravitational field. However, all analyses of the relativistic Doppler effect that I've seen only encompass the first two effects. Is there some model that includes all three?

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Jason R
Jason R
  • 61
  • 6

How does the relativistic Doppler effect model change if I want to include general relativistic effects also?

Derivations for the relativistic Doppler effect abound, which extends the description of the Doppler effect to include the effects of relativity in cases where the source or observer is moving at relativistic velocities. This is all pretty well-described in many sources that I have found.

But what if I would like to include the effects of general relativity instead? Assume the following scenario:

  • There is a stationary source on the earth emitting light at frequency $f$.
  • I launch a rocket that travels to orbit with some velocity profile $\mathbf{v}(t)$.
  • The rocket has a detector that continually observes the light source during its flight.
  • I would like to know the observed frequency of the light wave from the perspective of the rocket, as a function of time, $f'(t')$ (where $t'$ represents time in the rocket's reference frame).

I see three separate effects that would alter the observed frequency aboard the rocket:

  • The classical Doppler effect
  • Time dilation on the rocket due to special relativity
  • Time dilation on the rocket due to general relativity

All of these will change as a function of time as the rocket accelerates and as it moves within Earth's gravitational field. However, all analyses of the relativistic Doppler effect that I've seen only encompass the first two effects. Is there some model that includes all three?