Question

One of the key predecessors to Einstein's Relativity was another theory having to do with an Aether material. This substance was supposed to be the substrate that the universe is built upon. It was theorized to be nearly mass-less and occupy the entire volume of empty space.

So back in the 1800's before rocketry and space exploration were possible, why did they think they would be able to detect this substance? If the substance was supposed to have a lower density than that of hydrogen gas, wouldn't it immediately be buoyed up and out of the atmosphere the moment it was released? Is it even possible to detect a material like that while you are inside of a higher density medium...? From my perspective it seems like they were attempting the equivalent of measuring wind resistance while standing at the bottom of the ocean....so was this experiment ever valid in the first place?

If this experiment was not valid then does that put the Aether back on the table as a possible standard model theory?

Answer 1

The ether theory proposed a medium through which light traveled, and attempts like the Michelson-Morley experiment sought to detect it. These experiments failed to find evidence for ether, contributing to the acceptance of Einstein's theory of relativity, which redefined gravity and eliminated the need for ether.

Step-by-step explanation:

Ether Theory and Its Detection Attempts

In the late 19th century, the concept of ether, an all-pervasive substance, was hypothesized as a medium for the propagation of light and electromagnetic waves. This was before the theory of relativity introduced by Albert Einstein. A crucial experiment at that time, known as the Michelson-Morley experiment, was designed to detect the presence of ether by observing changes in the speed of light due to the supposed motion of Earth through this medium. The expected variations in light speed were not observed, suggesting that ether did not exist.

The idea behind detecting the ether was not akin to measuring wind resistance underwater, but rather attempting to measure the 'wind' (ether drift) of the entire ocean while being a part of it. The ether was believed to be a stationary frame of reference that filled all of space, even existing within higher density mediums like our atmosphere, rather than being a substance that could be displaced or 'buoyed up.' The failure to detect the ether led to the acceptance of Einstein's theories of relativity, which eliminated the need for ether as a medium for light and redefined our understanding of space and time.

Einstein's revolutionary idea was that gravity is not a force but the result of the curvature of spacetime caused by mass. His predictions on the motion of Mercury and the existence of gravitational waves have been confirmed experimentally, further establishing the accuracy of his theories and negating the need for ether in modern physics.