Validity of the Michelson-Morley experiment conclusion (1 Viewer)

[TrentsUnicorn]

I know that their conclusion included the following points:
-there was no background medium (ether) in space that moved relative to the Earth
-All moving objects receive light travelling at the same speed in a vacuum in all directions


What was the validity of this conlusion? Why?

 

[esaitchkay]

Here's a thread discussing the same question
http://community.boredofstudies.org/263/space/271713/validity.html
It seems that it's a contentious issue haha!

Here's what I think, but that could be 100% wrong would take it with a grain of salt haha:
A valid experiment is one that fairly tests the hypothesis, ensuring that there are no conceptual errors.
Now, if you look at what fizzy_cyst said in that link,
"Does the experiment measure what it is intended to measure?" (from syllabus anyways)
You could come up with either:
i) No it it does not measure what is intended, as the principle upon which the experiment is based (aether being absolute frame of reference; light being relative) is flawed and therefore you would not be measuring what is intended. Hence it is invalid.
ii) Yes it measured what was intended, as the idea of luminiferous aether (with one of the features being that it was stationary; i.e. absolute frame of reference) was widely accepted. Since it was the idea of an aether wind that was the basis of the experiment, it would be considered valid, when using 1887 physics knowledge.

I suppose it comes down to the marker's frame of reference, huh.
Hopefully they wouldn't ask that in an exam, though.

I'm keen for someone more knowledgeable to answer this, though.

 

[TrentsUnicorn]

Here's a thread discussing the same question
http://community.boredofstudies.org/263/space/271713/validity.html
It seems that it's a contentious issue haha!

Here's what I think, but that could be 100% wrong would take it with a grain of salt haha:
A valid experiment is one that fairly tests the hypothesis, ensuring that there are no conceptual errors.
Now, if you look at what fizzy_cyst said in that link,
"Does the experiment measure what it is intended to measure?" (from syllabus anyways)
You could come up with either:
i) No it it does not measure what is intended, as the principle upon which the experiment is based (aether being absolute frame of reference; light being relative) is flawed and therefore you would not be measuring what is intended. Hence it is invalid.
ii) Yes it measured what was intended, as the idea of luminiferous aether (with one of the features being that it was stationary; i.e. absolute frame of reference) was widely accepted. Since it was the idea of an aether wind that was the basis of the experiment, it would be considered valid, when using 1887 physics knowledge.

I suppose it comes down to the marker's frame of reference, huh.
Hopefully they wouldn't ask that in an exam, though.

I'm keen for someone more knowledgeable to answer this, though.

Thankyou for the link, that post had some good views on the topic. It seems that your right, it all depends on what you take "valid" to mean. Perhaps in my assignment I should make reference to both, seeing as they are both credible conclusions

 

[Amundies]

I know that their conclusion included the following points:
-there was no background medium (ether) in space that moved relative to the Earth
-All moving objects receive light travelling at the same speed in a vacuum in all directions


What was the validity of this conlusion? Why?

Big problem with your first point. They did NOT prove that there was no aether (or ether). I think quite a few people get this bit wrong. How I remember it is by remembering that there was "absence of evidence, not evidence of absence". Einstein then came along to prove that there was no need for an aether to exist.

 

[esaitchkay]

Big problem with your first point. They did NOT prove that there was no aether (or ether). I think quite a few people get this bit wrong. How I remember it is by remembering that there was "absence of evidence, not evidence of absence". Einstein then came along to prove that there was no need for an aether to exist.

I know that their conclusion included the following points:
no background medium (ether) in space that moved relative to the Earth

Whilst you are correct, Amundies, in saying that absence of evidence does not result in evidence of absence, the null result meant that:
i) the earth was stationary, relative to the aether (many scientists, following this experiment, suggested theories that said the earth dragged the aether along with it).
ii) the aether model was flawed

However, it is known that the Earth is moving, and since the velocity of Earth relative to the aether was found to be 0:
i) the aether model is flawed
ii) aether does not exist

However, I'm pretty sure you just misread what was quoted by OP and I'm being a grammar nazi

 

[Amundies]

Lol my bad, you are correct. I missed that entire last bit. Thanks for clarifying that up, I'd rather have a grammar nazi fix it up than OP become confused.