Whenever people are asked about experimental/observational proof of the constancy of c these two subjects almost invariably come up.

I don't understand how they prove the constancy of c.
Mind you, I am not saying:
"I don't understand how the observations prove it, therefore the conclusions must be wrong!"
I am saying:
"I don't understand how the observations prove it, therefore I want to understand."
Big difference there.

I will start with M-M.
From the observations made, the conclusion I would have come to is that either:
1.) There is no aether, and light does not need a medium to travel.
or
2.) Whatever medium light uses to travel, must be affected by the rotation of the Earth.
2a.) It is affected by the gravity, and the gravitational field of the Earth rotates with the Earth, therefore the medium rotates with the Earth as well.
or
2b.) It is affected by atmospheric drag. (which is much less likely, if even possible, due to the proagation of light in the vaccuum of space).

What am I missing here?

As for binary solar systems:
They say that the time it takes for the light to reach the Earth would vary with respect to whether the star is coming towards us or going away from us.
Why do they say that the there is no difference in time that it takes for the light to reach us.
I haven't found a source that explains that.
What observations were made that lead to this conclusion?

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The third (semi-related) thing that I am still unsure of is red shift.

I have been told that the reason for stars moving away from us displays a red shift effect is that the frequenct changes (in accordance with relativity) to compensate for the motion away from us through time dilation and length contration.
Speed = Distance/Time, therefore since Speed is a constant, then Distance and Time must change inversely proportionately to each other.

1.) Why is this more plausible than red shift occurring due to the Doppler Effect?
2.) If the frequency of the light decreases, but the speed of propagation stays constant doesn't that mean that the wave height must also increase? Have we seen that as the case? Is there a reliable way to verify that? Did I miss something here too?

Thanks

I’ll answer what I can:

Originally posted by one_raven
As for binary solar systems: ...

What I’ve read along these lines says that whether the star is coming towards us or going away from us, the measured velocity of its incoming light is c.

1.) Why is this more plausible than red shift occurring due to the Doppler Effect?

My understanding is that the Doppler contributes to the total redshift in your example. Specifically both the Doppler effect and the cosmological redshift (due to the stretching of the space the light travels through to get to you, as it travels to you) contribute to the total redshift in your example. I think in cosmology the cosmological redshift is sometime referred to as special relativistic time dilation. Time dilation and a redshift go hand-in-hand; for example, a 2% time dilation = a 2% redshift.

If you simplify the example to a retreating accelerating spaceship, then the Doppler effect and special relativistic time dilation contribute to the total redshift. Many books keep the example simpler still by discarding the Doppler effect (by pretending you have a string of assistant observers at rest with respect to you who record the ship’s properties like its velocity and clock rate as it passes them by, and then email you data) and talking about time dilation rather than its redshift substitute.

2.) If the frequency of the light decreases, but the speed of propagation stays constant doesn't that mean that the wave height must also increase?

I don’t see why it must. The ship’s recessional velocity relative to you increased (the ship accelerated) to decrease the frequency of its light as you observe it, but its photons are still emitted at c and travel at c and hit you at c from your perspective. No reason for the wave height to change.

one_raven,

You forgot one:

2c) Light uses gravitational fields as its medium of propulsion, and the Earth's gravitational field rotates, and moves, with the Earth.

Let c be speed of light, a constant.
Let f be frequency of light (cycles per second)
Let w be the wave length of light (distance per second)
Let * be the multiplier operator (times)

Then c = f*w ;is the result of eliminating time

f and w can vary all over the place without changing c.

If f goes up, w must go down and vice versa.

Agreed. Maybe one_raven meant wavelength, not wave height.

Hi,

Your opinion about Red shift is good one. That's good question.

I think: it is enough complex, so as our view could to incorporate also our world outlook.

Are you for materialism, or for idealism?

Unless and until your yes is the first one, we can to discuss more.

Eman S.

:confused: neither materialism nor idealism.. red-shift is due to communism...