Michelson Morley question. (1 Viewer)

[nirukk]

I am coming across a variety of Michelson Morley questions which are 3-5 marks. What's their aim for the experiment ? To test the presence of aether or to measure the speed of earth relative to aether ?

Then is their experiment valid? What's the results of the experiment ? I can just say null results. What's the impact on the scientific community ?

These question, how much I try I cannot understand or put into words. Help needed

 

[someth1ng]

I am coming across a variety of Michelson Morley questions which are 3-5 marks. What's their aim for the experiment ? To test the presence of aether or to measure the speed of earth relative to aether ?

Then is their experiment valid? What's the results of the experiment ? I can just say null results. What's the impact on the scientific community ?

These question, how much I try I cannot understand or put into words. Help needed

The bolded is correct.

For starters, their experiment WAS valid in that, in theory, if an aether, an absolute frame of reference existed, it SHOULD have been able to detect an interference pattern produced as the two beams of light would reach the detector at different times. The Michelson-Morley experiment was extremely precise and a fault in the apparatus is improbable.

However, there was a null result, in that, there was no predicted interference pattern produced suggesting that the speed of light was constant in all frames of reference. The test found produce no interference pattern when it was rotated, conducted at different location, different time of day or even different times of year.

This conflicted the aether model and opposed the view of the scientific community of the time and gave credibility to Einstein's Special Relativity, a theory that could explain the null result of the Michelson-Morley experiment by making speed of light constant in all inertial frames of reference and hence, space and time are variable.

 

[asianese]

NB: never say it disproved the aether.

You can't prove anything in science. Only 'provide strong evidence' etc.

 

[Kimyia]

NB: never say it disproved the aether.

You can't prove anything in science. Only 'provide strong evidence' etc.

This. It didn't disprove it, it just cast doubt upon it.

 

[someth1ng]

Are you guys referring to my response...?

 

[Kimyia]

Are you guys referring to my response...?

No, just making an additional point that the OP is sure to never state that it 'disproved' the aether.

 

[hayabusaboston]

"disproving" is perfectly valid and true, its PROVING that you cannot do. If you show through experimentation or otherwise a theory is incorrect, it is incorrect, there's nothing more to it. It is incorrect and therefore disproved.

ONce it is incorrect it cannot "suddenly" become correct.

 

[Kimyia]

"disproving" is perfectly valid and true, its PROVING that you cannot do. If you show through experimentation or otherwise a theory is incorrect, it is incorrect, there's nothing more to it. It is incorrect and therefore disproved.

ONce it is incorrect it cannot "suddenly" become correct.

True, but in the context of the MM experiment, you cannot say disproved because it had a null result.

 

[Demise]

True, but in the context of the MM experiment, you cannot say disproved because it had a null result.

Just say it gave way for Einstein's theory of special relativity. You don't need to say it disproved it, just say that the experiment could not show the existence of the aether since for the null result to exist:
1. The Earth would have to be stable (not moving) - BUT we know it is moving, SO
2. The aether does not exist in space.

 

[nirukk]

Yup that's what I thought since null result, you couldn't prove nor disprove. So it lead to Einstein's Relativity which showed there is no need for aether. Thanks everyone.

True, but in the context of the MM experiment, you cannot say disproved because it had a null result.

 

[Fizzy_Cyst]

NB: never say it disproved the aether.

You can't prove anything in science. Only 'provide strong evidence' etc.

Agree with the first sentence -- yep, you can say that the 'experiment did not detect any motion of the Earth relative to the aether' -- multiple reasons were thought up to account for this

Karl Popper - "no amount of experiments could ever prove a scientific theory, but a single experiment could disprove one"

 

[squishyau]

confused as to why different answers keep alternating the aim of the experiment between proving the aesther and measuring the speed of the Earth through it?

 

[barbernator]

confused as to why different answers keep alternating the aim of the experiment between proving the aesther and measuring the speed of the Earth through it?

They were measuring the velocity of the earth through the aether, and in doing so the experiment provided a null result as there was no change in the interference pattern of the light. Subsequently this provided experimental evidence that supported Einsteins theory of relativity, as the speed of light was constant in all inertial frames of reference. The presence of the aether was not proved or disproved, it just became superfluous as it had no effect on the speed of light.

 

[sprytex]

This is seriously one of the things I'm just not really understanding.

1. People suggest that there was no change in interference patterns - so was there an interference pattern to begin with?

2. I thought interference patterns only occurred when waves became out of phase. There was no interference pattern detected because the speed of of the two beams remained constant, correct?

3. If the distance of the two full-silvered mirrors (i.e, one was 2 mm further than the other from the half-silvered mirror) was changed, would it result in an interference pattern?

4. So, if this experiment was conducted with the two full-silvered mirrors the same distance apart from the half-silvered mirror, and the aether DID exist, then the change in velocities would result in a change in phase when the two beams were reunited and reflected to the detector and therefore result in an interference pattern?

5. If one of the beams was travelling parallel to the Earth's movement through the aether, would it would be travelling against it, forcing it to slow down more than one that would be travelling ~perpendicular to it?

6. The test found that no interference pattern was produced when it was rotated 90 degrees. Is this because the velocities of the two beams were constant and thus remained in-phase?

Thanks.