Simple & accurate aether experiment.

[arkain101]

I have an apparatus setup to test for the so called 'aether drift' that should be extremely easy to setup, offer accurate data with large and obvious change. Its so simple a child could do it.

Have we got any takers? Lets settle this for once and for all!

 

Purpose:

 

If earth were passing through a light medium (which I doubt we are :) ) there would be an observable doppler shift in a given light frequency depending on the velocity of the earth through the medium and the direction the light passed through that medium.

 

Materials:

 

*Using the tool for atomic spectra strip to test for redshift by measure the shift in bands.

 

 

*1 mirror.

 

*Light source

 

 

setupB]

 

Set up a light source that has a cover on it so it shines mainly in one direction.

 

Place a mirror approx 10m away from the light so the light shines on the mirror.

 

Set the mirror so you can see the light in the mirror when you stand behind your light source.

 

Set this apparatus in such a way so that the light path is in 90 degree arrangements. That is, measure each axis one at a time. x left x right,y left, y right, z up, z down. (or north south east west up down)

 

 

Proceedure:

 

angle A

Step 1: With the atomic spectra tool measure the spectra lines of the light, directly in front of the light.

 

Step 2: From the position behind the light source measure the spectra lines of the light source of the light that is reflecting off the mirror.

 

Compare any measureable doppler shift, that a so called "aether wind" would be expected to create.

 

Step 3: repeat proceedure in the next angle.

 

 

Summery and notes:

 

The experiment is to try and test any observable doppler shift of a given and consistant light frequency for a one way light path.

 

I assume the experiment could be arranged differently. That is, simply measure the spectra lines as your walk your way around a light checking for any change.

 

The use of a mirror could possibly create error in measurements, so it may be better to use a different method. However the mirror concept is what came to me at first.

 

Below is a quick little illustration of the experiment.

[arkain101]

Now that I rethink this over, I am not sure this will work. :) lol

[Boerseun]

The Michaelson-Morley experiment to detect the supposed ether-induced frequency shift operates in much the same way, but cross-wise with half-coated mirrors in the middle. The theory was that the initial light beam would be travelling in the x-axis, but halfway through the transmission it'll go through the half-coated mirror set up at 45 degrees, upon which some of the light would carry on in the x-axis, and the rest will be reflected into the z-axis. The, at a set distance, both beams (both x- and z- axis) would be reflected back upon which they'll meet again in the middle. The idea was that if the ether existed, then Earth's speed should be more in either the x- or -y axis, they won't be the same, with the nett effect that when the two seperated light beams meet up again, there should be visible interference where they meet, in the form of either black lines for destructive and brighter lines for constructive interference.

 

Alas, the Michaelson-Morley experiment showed no such results, and was instrumental in debunking the ether concept.

[CraigD]

… Set this apparatus in such a way so that the light path is in 90 degree arrangements. …

I perform essentially the experiment Arkain explains several times a year, when I get together with my small gang of astronomy fans, and play with homemade spectrometers. Some of us have Newtonian reflector telescopes, which have a 45° secondary mirror that reflects light 90° into the eyepiece lenses, while others have Cassegrains, in which light enters the eyepiece in the same direction it entered the telescope. The expected Doppler shift of the absorption lines when looking at known objects is the same regardless of which kind of reflector telescope is used. (I don’t have my own telescope, but I’m the one with the homemade slit spectrometer :cup:)

The Michaelson-Morley experiment to detect the supposed ether-induced frequency shift operates in much the same way…

The MM experiment was designed to detect differences (“fringe shift”) in the interference pattern of light from a common source following 90°-different paths, not a Doppler shift in frequency. There’s an important difference between measuring frequency (with a spectrometer) and interference patterns (with an interferometer). :(

[Leo]

Even if there is a stationary medium for EM waves, you can't detect a Doppler shift because both the emitter and the absorber of your setting go at the same speed. Good try anyway. And if you try devising more sophisticated tests involving relative speeds, then you have to deal with time dilation and synchronization, and in the end it's impossible to tell Minkowskian spacetime from Lorentzian mechanics.

[Boerseun]

Even if there is a stationary medium for EM waves, you can't detect a Doppler shift because both the emitter and the absorber of your setting go at the same speed. Good try anyway. And if you try devising more sophisticated tests involving relative speeds, then you have to deal with time dilation and synchronization, and in the end it's impossible to tell Minkowskian spacetime from Lorentzian mechanics.

That's why Michaelson-Morley placed the 45-degree half-coated mirror in the light's path, to split it away at 90 degrees. The purpose of this is to see if there's a difference in the two (x,y) axes. If there was a stationary medium, Earth won't be moving through it at the exact same speed in all dimensions.

[Qfwfq]

Even if there is a stationary medium for EM waves, you can't detect a Doppler shift because both the emitter and the absorber of your setting go at the same speed.

This is true if the two directions coincide, false when they are perpendicular. The only difference in principle beween Arkain's setup and M&M is that they used interferometry which is sensitive to far slighter changes.

[CraigD]

The only difference in principle beween Arkain's setup and M&M is that they used interferometry which is sensitive to far slighter changes.

I think there’s a great difference in principle between Arkains’s setup (a spectrometer, or “frequency measurer”) and the MM experiment’s interferometer.

 

The MM interferometer essentially measures change in the distance traveled by light along perpendicular paths, by measuring the change in the interference of the two wave fronts – that is, a change in their relative phase. Because the wavelength of the light measured is short compared to the size of the apparatus, and a difference of only a small fraction of that wavelength produces easily visible changes in the visible interference pattern, their setup was capable of detecting the very slight differences in path length due to the difference in Earth’s velocity at time t vs. t+6 months relative to a fixed framework. When it didn’t, it earned the honorific “most famous failed experiment ever”.

 

Spectronomy was a well-established field (about 200 years old) in the 1880s, as were reflector telescopes of various geometries, so Michelson and Morley would have been aware that light doesn’t change color/frequency when it is reflected in a perpendicular direction, and wouldn’t have put effort into an experiment attempting to show otherwise.

[Qfwfq]

I suppose I was reasoning as if an increase in elapsed time would imply an increase in period. :) If you boil it down, it's really a matter of measuring lengths and times. I'm quite sure M&M knew optics very well, they obviously chucked everything except interferometry out the window.

 

I don't find what you say about previous knowledge all that conclusive, telescope design is in the end based on interfence too. It's a matter of the setup and method being sensitive enough to the specific matter of investigation. Even if devices had been in use, of design reliant on supposing elapsed time independant of direction, they would have been aware that the discrepancies could not have been noticed. It's a bit like the reason the difference between time zones is called jet-lag and not sailboat-lag.