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Doppler shifting happens because motion tends to shrink and stretch waves whether it is sound or light. The constant speed of light doesn't effect the Doppler shift.
That seems counterintuative. But then so does most of quantum physics to me! How can the waves be stretched by motion without the speed being effected?
The speed of light is always constant, regardless of the position and relative speed of the observer.For example, apparently if you were in a spaceship travelling incredibly fast and you were passed by a ship travelling at a similar speed in the opposite direction and at the same time you both passed a third stationary ship then the light from your headlights would be travelling at exactly the same speed relative to all three ships. Because speed is equal to distance divided by time then, to make this impossible thing happen, time and space will both become distorted to accommodate it. So, the speed of light is ALWAYS constant.In that case how come light is subject to the Doppler effect and gives us Red Shift?
λ = c/νSince c is constant and invariant, if the frequency ν is lower, wavelenght λ is greater and you have red shift.
Hi VernIf you run along dropping the cookies doesn't that mean that the leading edge of the line of biscuits is approaching you at a faster speed?
I only just sort of had a bit of a grasp of what I possibly thought might be happening, maybe.
I'm completely confident I've got this speed of light and Dopplar thing nailed! The only thing that's separating me from Einstein is that he has neater hair.
This profound fact was recognized by H. Ziegler in 1906, two hundred years before it would finally be realized by the funded Physicists. We now know that this is the correct cause of the phenomena of relativity.
Vern - I've looked at the page you linked to in your first reply and something is puzzling me:QuoteThis profound fact was recognized by H. Ziegler in 1906, two hundred years before it would finally be realized by the funded Physicists. We now know that this is the correct cause of the phenomena of relativity. Two hundred years? I know about time dilation but are we realy in 2106 already?
I don't accept any doppler wave answer due to the fact you absolutely can outrun sound.
Now consider Doppler shift. If I send out a light pulse every second, you will receive a pulse every second if I'm not moving. If I move away from you, and the speed of light is constant, the pulses will arrive at slightly longer intervals because each pulse has further to travel. So the perceived frequency of a receding source is lower, and of an approaching source is higher, than the frequency received when it is stationary.Wavelength L = c/frequency, so L increases for a receding source and vice versa. The Pound-Rebka experiment was a neat proof of all this. https://en.wikipedia.org/wiki/PoundĖRebka_experiment