How did the aether model violate the principle of relativity? (1 Viewer)

[WEMG]

The Jacaranda explanation is not making sense to me:

In the late nineteenth century, belief in the aether posed a difficult problem for the principle of relativity, because the aether was supposed to be stationary in space and light was supposed to have a fixed velocity relative to the aether. This meant that if a scientist set up equipment to measure the speed of light from the back of a train carriage to the front, and it turned out that the light was slower than it should be, the train must be moving into the aether. Put another way, this optical experiment provides a way to violate the principle of relativity where no mechanical experiment could.

Can someone please explain that or explain how the aether model violated the principle of relativity?

 

[ohexploitable]

It meant that light could travel at different speeds for different frames of reference. If light traveled at c relative to aether and an observer was travelling at c/4, the light would appear to travel at 5c/4 relative to the observer, hence, violating the principle of relativity.

 

[annabackwards]

The Principle or Relativity states that you cannot determine whether your intertial frame of reference is moving or stationary unless you refer to an outside frame of reference.

The earth is an inertial frame of reference (it is not accelerating). Light on the earth is also an interial frame of reference (moves at a constant speed;l not accerlating) so the earth-light frame of reference can be considered ONE intertial frame of reference.

According to the principle of relatively, no matter what experiment you do the speed of light on earth would have to be the same (you are NOT referring to an outisde frame of reference). Otherwise you could tell you can tell you are moving which violates the Principle or Relativity.

If we did somehow detect a change, then that would suggest that the earth WAS moving into the aether. But this is not possible because the experiment is only done in ONE interial frame of reference - the earth-light frame of reference ie it violates the Principle or Relativity.

 

[cutemouse]

Funny thing is that the interference effect isn't even in the syllabus but you're expected to mention it when explain the Michelson-Morley experiment. Talking about rote learning ==; You learn about it in 1st year university Physics (PHYS1B if you're at UNSW).

 

[jamesfirst]

It's pretty confusing first but it's easy

 

[Jonneeh]

Funny thing is that the interference effect isn't even in the syllabus but you're expected to mention it when explain the Michelson-Morley experiment. Talking about rote learning ==; You learn about it in 1st year university Physics (PHYS1B if you're at UNSW).

Didnt we learn about Interference effect in year 11 the waves and emr topic xD

 

[ohexploitable]

Didnt we learn about Interference effect in year 11 the waves and emr topic xD

Yeah, I remember learning about constructive and destructive interference early in Year 11.

 

[cutemouse]

Didnt we learn about Interference effect in year 11 the waves and emr topic xD

That's different.

If you shine a monochromatic light source behind two slits then you will observe an interference pattern. It's because light acts as a wave in this case.

 

[jamesfirst]

You can also refer back to Einstein's thought experiment with mirror and train.

It's in the syllabus dot point on the 3rd column.