My journey into the realm of Relativity (Einstein, Newton, Galileo, et. al.) began with a simple question:

Can the speed of sound,c, be substituted for speed of light,c, in the Michelson-Morley interferometer formula?

That is, T = L /(c-v) + L /(c+v). It turns out that the answer (after my online investigations) is yes. The symbol,c, is applied

to both types of waves. While c as the speed for light is 300,000 km /sec , and c as the speed for sound is approx. 300 m /sec.

Additionally, the violation of Galilean invariance by all waves leads to my use of this formula for an "echo"; not T = [2L] / c .

From this I hope to derive new definitions of absolute motion and simultaneity, with experiments using sound instead of light.

This will be contrary to Einstein's Relativity Postulates. In other words by finding time,T, by means of a single clock, then I can

algebraically rearrange the above mentioned formula to find v, the velocity or the absolute motion of an object.

For additional details on this topic, see my posts:

http://stargazerslounge.com/topic/161871-michelson-morley-experiment-speed-of-speed-c/