2 of 36

Relative

Write now Article Tools

Page 4 of 6

of the beam, heat variations, or even vibration in the room, Michelson's successive interferometers became more and more elaborate.

Continuing his experiments with Ed Morley at the Case School of Applied Science in Ohio, the beams of light were reflected by an array of multiple mirrors (increasing the mirrored beams' combined light path to over 32 meters); the mirrors were in turn set on a large granite (or concrete) block; and that was set on a "bath" of mercury to damp any extra vibration when the thing was rotated. I even have it by word of mouth that Michelson once ordered all carriage traffic and steam engines in Cleveland stopped one afternoon to further eliminate any local vibration through the Earth's crust.

But, still, nothing.

This experiment, and its exotic variants (consider Sir Oliver Lodge's efforts with his "ether machine"), have since been preformed hundreds of times - once by maser in 1958. In "Carrying the Fire," Michael Collins wrote of repeating a version of it while in lunar orbit during Apollo 11 in 1969.

But even up to the 1960s the fringing effect was never more than .01 to .004 of the expected value.

But even by the 1880s, theorists jumped on it. The "Titanic" that was the ether theory was sinking hard by the bow leaving plenty of job openings for a new crew. The death of the old school left nothing but fertile opportunity for a fresh generation of scientific revolutionaries.

George Francis Fitzgerald and Hendrik Anton Lorentz speculated that the "pressure" of the passing ether was shortening the apparatus (and everything else on the planet, including the planet) to a degree that exactly cancelled out any interference fringing.

Even Albert Einstein considered this idea for a while in "The Electrodynamics of Moving Bodies," until he realized that something else was going on.

But his was a rationalization you really need to make for yourselves if the conclusion of General Relativity is to make any sense. And, believe it or not, if you've followed me so far, you have all the evidence you need to form an opinion about relative time.

Let's review:

(1) The speed of light is independent of the emitter's speed. This is from investigations that proceeded after James Bradley's initial 1725 observation. All that changes on the light beam is the Doppler shift of its frequency and wavelength, and these cancel, too. That is (let l be wavelength (as this system doesn't do lambdas)), then f x l = f' x l' = c, no matter what.

(2) The speed of light through space

• << previous page
• 1
• 2
• 3
• 4
• 5
• 6
• next page >>

Add your voice

Know something about Is time real or relative??
We want to hear your view. Write now!