# Doppler shift

1. Dec 26, 2005

### Hydr0matic

What is the difference in magnitude between the effects of normal doppler effect and doppler effect in accelerated frames, e.g. when the (light)source is accelerating wrt the observer? What is the formula for doppler effect in accelerating frames?

2. Dec 26, 2005

### marlon

What do you mean by normal Doppler effect ?

When velocity of source/observer is not constant, the shift in frequence will be time dependent. It is expressed by the v-formula that depends on time, initial velocity and acceleration.

marlon

3. Dec 26, 2005

### Hydr0matic

By normal I mean with constant relative speed.
Since we are dealing with light and spacetime I just assumed that, like in relativity, accelerated frames behave differently.
http://www.du.edu/~jcalvert/phys/doppler.htm
Surely, doppler shift from a lightsource with relativistic and extremely accelerating speed isn't governed by the classical doppler formula?

4. Dec 27, 2005

### marlon

This can be both the "classical" version or the relativistic version of the Doppler effect, depending on how close this velocity is to c.

Well, in the case of high velocities, the principles of special relativity need to be applied.

marlon

5. Dec 27, 2005

### Tide

To see what effect acceleration has on the frequency/wavelength of light you can invoke Einstein's (gravitational) equivalence principle. Light from a massive object would be seen as red shifted by a distant observer and to an observer closer to the massive object light from a more distance source would be seen as blue shifted.