Could the Michelson & Morley Experiment Have Used Electrons Instead of Light?

In summary, the conversation discusses the concept of the speed of light being constant from any frame of reference, as proven by the Michelson and Morley experiment. The experiment was carried out using light because it is the subject of Maxwell's equations. The possibility of using other particles, such as electrons or muons, in the experiment is discussed but ultimately deemed not feasible due to their non-constant speeds. The relationship between the speed of light and the rest frame of a photon is also mentioned, but not fully understood.
  • #1
A Dhingra
211
1
Michelson & morley experiment...

hi there...

We say that the speed of light is constant when seen from any frame of refrence because the ratio of length and time measured from moving and rest frame is same.
Also by Lorentz transformation L= L1 $ (L1 and T1 are in the moving frame and $ represents gamma)
And T1 =T $
So L/T =(L/$)/T$ =L/T ($ 2 )
1 =(1- v2 /c2 )
So v = c…..
This proves that at the speed of light a body, be it any, not necessary a photon, appears constant from any of the frames.

In the Michelson and Morley experiment , if instead of light, electron would have been used what would the results have been ? will the desired shift be observed or not…… would that suggest something about the non existent ether…….??
Let us assume the speed of electron is taken to be on very close to that of light (hence introducing relativistic effect) and the same experiment if repeated with speed of 300 km/s or more…… what would be the result in the two cases?

According to Lorentz transformation I think the result would have been a positive ….. give expected fringe shift because only the velocity of light is constant from any frames. So would that not serve as a positive sign for ether hypothesis……??
Moreover I wish to ask why the experiment was carried out using only light and no other particle like elctron…?


Thanks in advance...
 
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  • #2


A Dhingra said:
This proves that at the speed of light a body, be it any, not necessary a photon, appears constant from any of the frames.
This doesn't makes sense. See the FAQ: [thread]511170[/thread].

Moreover I wish to ask why the experiment was carried out using only light and no other particle like elctron…?
The Michelson-Morley experiment was carried out with light because that is the subject of Maxwell's equations. Also note, electrons were not shown to exist until Thomson's 1896 experiment. The MM experiment was performed in 1887.
 
  • #3


It also makes no sense to use electrons, because no one is claiming that the speed of electrons are constant and isotropic! What would we be trying to show here?

Zz.
 
  • #4


can you please tell me will the result change if electron beam is used instead of light beam?
 
  • #5


D H said:
This doesn't makes sense. See the FAQ: [thread]511170[/thread]..
how is the speed of light being same seen from any frame, related to rest frame of photn as you have mentioned the link... please exlpain the relation.?

thanks
 
  • #6


A Dhingra said:
D H said:
A Dhingra said:
This proves that at the speed of light a body, be it any, not necessary a photon, appears constant from any of the frames.
This doesn't makes sense. See the FAQ: [thread]511170[/thread].
how is the speed of light being same seen from any frame, related to rest frame of photn as you have mentioned the link... please exlpain the relation.?

thanks
Perhaps I misread your initial statement. I read "This proves that at the speed of light a body ..." as meaning from the perspective of something moving at c.


A Dhingra said:
can you please tell me will the result change if electron beam is used instead of light beam?
This makes no sense. Is the speed of a car moving down a highway the same to all observers? (No, isn't.)
 
  • #7


what if the car moves at the speed of light... (though i know this is not possible due to various reasons)... will its speed not appear constant from any rest or uniformly moving frame??...

and this is what that statement was... but then the connection u gave with photon's rest frame is still not clear...

Also please explain why won't the speed be of a BODY moving with c same to all observers( ignoring the fact that attaining this speed means having infinite mass but zero length )...
or is it that this limit ensures that only photon appears to move wiht c by all observers...
if true ...i guess i got it...
 
  • #8


Please, stop using so many periods! It makes your posts very annoying to read. One period denotes the end of a sentence. Three may be used to indicate an omitted part of a quote. Any other usage is not helpful in communicating your thought.

Anything which moves at c in one frame will move at c in all frames. Neither electrons nor cars ever move at c, so using them in a variant of the Michelson Morely experiment wouldn't make sense. In principle you could use gluons.
 
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  • #9


Sorry. I won't do that again.
 
  • #10


how about muons (or so)? will they do?
 
  • #11


Muons also have mass, so they travel at v<c.
 
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  • #12


Ok.Thanks.
 

What is the Michelson & Morley experiment?

The Michelson & Morley experiment was a scientific experiment conducted in the late 19th century to measure the speed of light and to test the existence of the hypothetical "ether" that was believed to be the medium through which light waves traveled.

Who were Michelson and Morley?

Albert A. Michelson and Edward W. Morley were American physicists who conducted the famous experiment in 1887 while working at Case Western Reserve University in Cleveland, Ohio.

What was the purpose of the experiment?

The purpose of the experiment was to measure the speed of light and to test the prevailing theory of the time, which stated that light waves traveled through a medium called the "ether".

What were the results of the experiment?

The experiment yielded unexpected results, as it showed that the speed of light was constant in all directions, regardless of the direction and speed of the Earth's rotation. This contradicted the theory of the "ether" and paved the way for Albert Einstein's theory of special relativity.

Why is the Michelson & Morley experiment important?

The Michelson & Morley experiment is considered one of the most important experiments in the history of physics because it provided evidence for the theory of special relativity and challenged the prevailing beliefs about the nature of light and the universe. It also paved the way for further experiments and theories in the field of physics.

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