If the ether had been proven real by the Michelson-Morley experiment, it would have meant that light requires a medium to propagate through, rather than being able to travel through a vacuum. This would affect the second law of special relativity, which states that the speed of light is constant and independent of the motion of the light source. The speed of light would depend on the direction of Earth's motion through the ether medium.

1. Explain the results of the Michelson-Morley experiment if the ether had been a reality? What
significance would this have had to the speed of light?
Solution
The Michelson Morely experiment was conducted to prove the existance of a uniformly
pervasive ether medium. As the experiment was a failure we can conclude that the universe is
vaccuum but not ehter.
Now if it were a reality, then that means for the propagation of light a medium is required. That
means speed of light will be different for different media. This will effect the validity of second
law of speacial theory of relativity which is to say that the speed of light is same across and is a
universal constant. Speed of light would also depend on the direction of earth's motion.