[jimster]

My roommate invited me to go scuba diving at Anacapa Island with him. He had a boat at Channel Islands, near Oxnard. Anacapa Island is about 20 miles offshore. As we motored out, the shoreline disappeared, but you could still see the hills behind Oxnard, which looked like they were sinking beneath the horizon, until just the peaks, then nothing. Looking forward, the top of the Anacapa first became visible, then lower and lower until we could see the shoreline. The reverse happened on the trip back, first seeing the tops of the hills inland behind Oxnard, then more and more became visible until we could see the shoreline. The air was crystal clear and the sea was calm.

I want to diagram what I saw from the side, where did the light rays travel?

Can anyone explain how and why the light rays work to make this happen on FE? I am trying to diagram how this would work at various distances on FE. How can I see things beyond Oxnard and not be able to see Oxnard? Why does it look like the peaks sink into the ocean? I can see the tops of the hills beyond Oxnard, but I can't see Oxnard. I can see miles across the water, so no wave or swell blocked my view.

     /\
   /   \
 /      \                                                                                           
/        Oxnard______________________________boat____________
                                                                                                                                                         
Please show how the light rays travel when I am about 5 miles from shore such that I can see the sea for miles and the tops of the hills behind appearing to be right on the surface, yet not see Oxnard.

[jack44556677]

I will not attempt to best your ascii art, however I think I can help you understand.

There is a density gradient in our air that causes light to bend (convexly) towards the water as the light travels through it.

The light from the bottom of distant objects is diverted into the water first because of this (primarily/initially)

[stack]

I will not attempt to best your ascii art, however I think I can help you understand.

There is a density gradient in our air that causes light to bend (convexly) towards the water as the light travels through it.

The light from the bottom of distant objects is diverted into the water first because of this (primarily/initially)

At what distance is the light diverted from the bottom of objects? What calculation do you use to predict when an objects bottom goes missing due to diverted light?

[AATW]

I will not attempt to best your ascii art, however I think I can help you understand.

There is a density gradient in our air that causes light to bend (convexly) towards the water as the light travels through it.

The light from the bottom of distant objects is diverted into the water first because of this (primarily/initially)

So, an issue I have with some FE reasoning is it seems to be a combination of claiming that the earth must be flat because ships don't really sink below the horizon (Rowbotham claimed that ships going below the horizon can be "restored" by optical magnification which is patently false) and claiming that there are optical effects which make it appear that things are sinking below the horizon when they are not.

The former is clearly not true - sure, sometimes small boats which are too small to be seen with the naked eye at a certain distance can be seen by optical magnification, but you can easily find footage and images of boats clearly sinking below the horizon zoomed in in such a way that clearly they can't be restored.

If the latter is true then your claim is basically that the earth is flat and any observations you make which fit better with a globe earth are simply optical effects. If so then how you do you determine the shape of the earth?

[SteelyBob]

I will not attempt to best your ascii art, however I think I can help you understand.

There is a density gradient in our air that causes light to bend (convexly) towards the water as the light travels through it.

The light from the bottom of distant objects is diverted into the water first because of this (primarily/initially)

I think we can all agree that there's a density gradient in the air - air density reduces with increasing altitude.

If I'm, say 10 feet above the sea level, observing an object that's also 10 feet above the sea, then it seems we can all also agree that, contrary to Rowbotham as AATW points out, as I move further away from that object then it will progressively appear to dip lower and lower until such a time as it goes below the horizon.

I would say that's because the earth is curved. You're saying it's because the light from it curves down due to the 'density gradient'. But if I'm 10 feet above the water, and the object is also 10 feet above the water, then the air density in a straight line between us is constant, so why would the light curve?

[Peter Winfield]

I think we can all agree that there's a density gradient in the air - air density reduces with increasing altitude.

I haven't heard specific claims to the contrary, but this would imply that if you go high enough you would reach (almost) empty Space. Space is disputed by some FE advocates, who insist that a dome is required to hold the atmosphere in (because there is no Gravity).

[SteelyBob]

I think we can all agree that there's a density gradient in the air - air density reduces with increasing altitude.

I haven't heard specific claims to the contrary, but this would imply that if you go high enough you would reach (almost) empty Space. Space is disputed by some FE advocates, who insist that a dome is required to hold the atmosphere in (because there is no Gravity).

Ah, they don't think gravity exists, but they do (mostly) think the earth is accelerating upwards at 1g, so the density gradient is consistent with that at least. Don't ask about the need for an enormous power source, or the absence of explanation for why and how the planets and stars accelerate at the same rate. Just go with it. 

[jimster]

Thank you Jack for the direct specific explanation. I do hope you read this and continue my exploration into making sense of this on FE.

Oxnard is at sea level and the boat is at sea level. Air should be equally dense. Why did the light ray not travel straight to me? Where did it go?

I would expect density bending to be a gradual proportionate process, but the top of the peak was undistorted with a sharp cutoff. How can that be?

[SteelyBob]

I will not attempt to best your ascii art, however I think I can help you understand.

There is a density gradient in our air that causes light to bend (convexly) towards the water as the light travels through it.

The light from the bottom of distant objects is diverted into the water first because of this (primarily/initially)

Hello Jack. Still awaiting a reply to my question:

But if I'm 10 feet above the water, and the object is also 10 feet above the water, then the air density in a straight line between us is constant, so why would the light curve?

[jack44556677]

@aatw

If so then how you do you determine the shape of the earth?

Aye, that's the rub! You've got it - great question! 

There is only one way to determine the shape of physical objects with certainty and it is not "look at shit"  [the sky, the boat, the horizon etc.] followed by declaration on what you are seeing.  No empirical science is conducted by simply looking (aside from the establishment of natural law, the sole caveat)

[jack44556677]

@peter

I do hope you will return, but I understand if you do not.  You may want to give the sister site a whirl (search the forums here for it) too.

I am one such "space skeptic/denier", and have concluded that not only is "space" complete fiction (and has its origins, indisputably, in that medium) but that it cannot exist in the reality we study.  It would violate many well established natural laws which have stood for centuries without contest.

The gradient is caused by weight (an intrinsic and inexorable property of all matter) and exists in every container of gas (great and small) for the same reason.  It is a popularly taught misconception that the gradient proves "there's vacuum up there!", and part of the stupidest mythology that mankind has ever concocted (and that is no small feat) - "the infinite sky vacuum".

[jack44556677]

@jimster & steelybob

Air should be equally dense. Why did the light ray not travel straight to me? Where did it go?

Great question(s)!  It went into the water due to interaction with matter on route, as I explained.

Here is a video that shows a demonstration of what is occurring.  We can discuss the why after that!

I would expect density bending to be a gradual proportionate process, but the top of the peak was undistorted with a sharp cutoff. How can that be?

Because the light is still reaching your eyes! The other reason is that when looking upward at an angle, you are looking through much less matter (the same is true in reverse, and is one of the chief reasons we can see farther from higher up)

[SteelyBob]

@jimster & steelybob

Air should be equally dense. Why did the light ray not travel straight to me? Where did it go?

Great question(s)!  It went into the water due to interaction with matter on route, as I explained.

Here is a video that shows a demonstration of what is occurring.  We can discuss the why after that!

I would expect density bending to be a gradual proportionate process, but the top of the peak was undistorted with a sharp cutoff. How can that be?

Because the light is still reaching your eyes! The other reason is that when looking upward at an angle, you are looking through much less matter (the same is true in reverse, and is one of the chief reasons we can see farther from higher up)

That entire point of that experiment is that the laser travels through a medium with varying refractive index. See here for a more detailed explanation:

https://sciencedemonstrations.fas.harvard.edu/presentations/bouncing-light-beam

And yes, the experiment elegantly demonstrates atmospheric refraction. But the reason we get refraction is because the air has, as you say, a density gradient - if you draw a straight line through a curved air mass it encounters different densities at an angle, and so refraction happens. If the world was flat that wouldn’t happen - as per my previous comment, if you’re at 10 feet, and the thing you’re observing is at ten feet, the density is constant, regardless of the gradient in atmospheric pressure.

So, again, where in your model of what’s going on is there a gradient that could cause refraction?

[Iceman]

No empirical science is conducted by simply looking (aside from the establishment of natural law, the sole caveat)

What exactly are you trying to say here?

[Elyn95]

That entire point of that experiment is that the laser travels through a medium with varying refractive index. See here for a more detailed explanation:

https://sciencedemonstrations.fas.harvard.edu/presentations/bouncing-light-beam

And yes, the experiment elegantly demonstrates atmospheric refraction. But the reason we get refraction is because the air has, as you say, a density gradient - if you draw a straight line through a curved air mass it encounters different densities at an angle, and so refraction happens. If the world was flat that wouldn’t happen - as per my previous comment, if you’re at 10 feet, and the thing you’re observing is at ten feet, the density is constant, regardless of the gradient in atmospheric pressure.

So, again, where in your model of what’s going on is there a gradient that could cause refraction?
[/quote]

But in this experiment the line is not being drawn through a curved mass, the tank is flat and the line still curves? If he was shining it through a globe goldfish bowl then I would concede your point, but here the experiment seems to back up the hypothesis of the curvature of light through a flat densiity gradient.

[Tumeni]

There is only one way to determine the shape of physical objects with certainty and it is not "look at shit"  [the sky, the boat, the horizon etc.] followed by declaration on what you are seeing.  No empirical science is conducted by simply looking (aside from the establishment of natural law, the sole caveat)

You tell us there is "only one way" then fail to specify the way.

You tell us what way is not the way. You hint that something is required in addition to looking at stuff, but fail to specify what that something is.

Do you have anything to add?

[SteelyBob]

That entire point of that experiment is that the laser travels through a medium with varying refractive index. See here for a more detailed explanation:

https://sciencedemonstrations.fas.harvard.edu/presentations/bouncing-light-beam

And yes, the experiment elegantly demonstrates atmospheric refraction. But the reason we get refraction is because the air has, as you say, a density gradient - if you draw a straight line through a curved air mass it encounters different densities at an angle, and so refraction happens. If the world was flat that wouldn’t happen - as per my previous comment, if you’re at 10 feet, and the thing you’re observing is at ten feet, the density is constant, regardless of the gradient in atmospheric pressure.

So, again, where in your model of what’s going on is there a gradient that could cause refraction?

But in this experiment the line is not being drawn through a curved mass, the tank is flat and the line still curves? If he was shining it through a globe goldfish bowl then I would concede your point, but here the experiment seems to back up the hypothesis of the curvature of light through a flat densiity gradient.
[/quote]

One of my pet hates on this forum is when people don’t admit they are wrong, so I need to be honest with myself and admit that you’re dead right - my apologies. A poor example of the point I’m trying to make. Happy to stand corrected.

[scomato]

Light can bend when it comes into contact with molecules that disrupt its linear path. This is how mirages work, with the rising action of hot air causing the light distortion. The light from above the road, that would have otherwise missed your eyes completely, are deflected upwards into your eyes creating the illusion. 



Light also gets refracted when it passes through other changes in the air. Like in the exhaust of a jet engine.



Refraction of Light is also responsible for the awesome effect you get using the process of Schlieren Imaging, which uses the refractive variation in light to 'see' perturbations in air pressure and wind.



Light rays can also be bent on cosmic scales, "the graceful arcs at the center of this image from the Hubble Space Telescope are actually the distorted light of distant galaxies, twisted to form an "Einstein ring" by the gravitational influence of the closer galaxy cluster SDSS J0146-0929."

[jack44556677]

@scomato

The last of your examples is wrong.  The rest are right!

The only thing that can alter lights path is direct interaction with matter.  "Gravitational lensing" is fiction with only clear experimental/scientific/demonstrative refutation (no support whatsoever).

[scomato]

@scomato

The last of your examples is wrong.  The rest are right!

The only thing that can alter lights path is direct interaction with matter.  "Gravitational lensing" is fiction with only clear experimental/scientific/demonstrative refutation (no support whatsoever).

Well, if we want to get pedantic about it, gravity doesn't alter Light's path through space, like interaction with matter does. Gravity warps the space that light is travelling through itself, as far as the photon is concerned it has never changed course. It is more akin to drawing a straight line on a piece of paper, and then bending the paper.

Can you kindly cite any work that clearly refutes gravitational lensing?


You are dead wrong with the claim that the only thing that can alter a light's path is interaction with matter. Experiments at LIGO (which is just a giant Michelson Interferometer, described below) proved the existence of gravitational waves that are constantly passing through the earth, like ocean waves rocking a boat at sea.





It is kind of an interesting round-circle, Michelson and Morley originally conducted their original experiment (which won them the 1907 Nobel Prize) to disprove the Aether theory (https://en.wikipedia.org/wiki/Michelson%E2%80%93Morley_experiment), and then over a hundred years later the same method was used to prove the existence of gravitational waves.



This 'blip' that is simultaneously observed at both LIGO stations is the interference pattern caused by gravitational waves rocking through the planet. This is irrefutable proof of gravity's effect on light - but nobody has seriously argued against gravity effecting light since Newtonian physics.



It is funny, because the proponents of the Aether Theory were kind of on the right track, sort of. But instead of an Aether what there actually is, is a gravitational background.