"We know that light travels in a vacuum without anything present". Wait do we?

posted 105 days ago by TurnToGodNow 105 days ago by TurnToGodNow +12 / -2

That's what they tell us. Light can travel through a vacuum with nothing in it. And maybe so but what is the evidence?

So I looked up the best vacuum on planet Earth. It contains 2.5 million molecules of air per cubic cm. This is said to replicate conditions between stars. So how then can we say we've ever tested light waves going through "nothing". We haven't.

To test the validity of my suspicions I've asked the science guys on reddit if they have an answer for this. The first few responses have already been hostile and that usually indicates this is one of those issues they simply don't have a good answer for. I was very polite in my question btw, so no I didn't provoke anybody, this is all on them.

We'll see how it goes. I'm open to a good explanation of why this is a valid test, but this light has 2 million molecules to interact with ever cubic cm it propagates, so you didn't rule out matter.

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– TurnToGodNow [S] 2 points 94 days ago +2 / -0

I don't think i understand what you mean by this. How do you think air is causing a fringe pattern in a stationary rlg (in a room with no wind)?

I mean the air is moving the wave over at the same speed of Earth's rotation then. So how could there be a noticably difference between a rotating Earth with rotating lower atmosphere and no rotation measured with this? There can't be.

But this is the core difference between mmx (detected no cosmic linear motion) and gale pearson (detected local/earthbound rotational motion)

I don't know gale pearson yet. But from what I understand MMX was designed to look at earthbound rotational motion as well.

However if that loop is intended to spin on the spindles that is certainly going to introduce vibration (and hence fringe) in and of itself

Yes it is intended to be mover on those wheels or spindles. Not sure how much vabration was in the system, ask Mr Wang who made it.

The device is intended to observe Sagnac and look at how much linear motion contributes to the effect over a standard rotational only setup.

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– jack445566778899 1 point 93 days ago +1 / -0

I mean the air is moving the wave over at the same speed of Earth's rotation then.

Just to clarify - you think the interference pattern found in stationary rlgs and the gale pearson are due to wind far above the detector? If so, would you not expect the interference pattern to vary when the wind speed (inevitably) does?

So how could there be a noticably difference between a rotating Earth with rotating lower atmosphere and no rotation measured with this?

If you are saying that no interference pattern is detected with the wacky spinning spindle rlg - then that is certainly interesting. I wonder if the pattern returns as you slow down the rotation of the spindles - since without that rotation, this seems to be a standard rlg setup.

But from what I understand MMX was designed to look at earthbound rotational motion as well.

Perhaps, but it failed to find it in any case - presumably due to its configuration (straight legs, right angles)

Not sure how much vabration was in the system, ask Mr Wang who made it.

Perhaps it cancels out / affects both paths equally - but it would certainly affect the fringes.

The device is intended to observe Sagnac and look at how much linear motion contributes to the effect over a standard rotational only setup.

And what was the result?

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