A discussion on TFES forum

[brimstoneSalad]

You would need to use a level and a camera to compare the horizon in photographs.

Well, this is a photo from the Mount Everest!
[...]
You can clearly see that the apparent horizon is way above the eye level!
See the problem? Your statement is unfalsifiable.

You asshole, did you even read that one fucking line? Or were you too stupid to understand any of the words in the sentence?

You would need to use a level and a camera to compare the horizon in photographs.

You would need to use a level and a camera to compare the horizon in photographs.

threehorizons.jpg

threehorizons.jpg

(fixed)

It's a photograph you moron. You have no idea what angle or frame the camera is using. It's easy to move the horizon around by slightly changing the camera position and angle.

You're so stupid this is painful to me.

Here's how you test it, dipshit:

1. Level the camera with a proper level device (like with a bubble) -- you will need a tripod too, obviously (it might go without saying if you weren't a complete moron). You'd also want to use consistent lens and focus etc. and compass/GPS to make sure you're at the same ground position and facing the same way.
2. Find a single location with a simple horizon (ideally ocean to it's level and unobscured) where you can elevate the camera to compare two different altitudes at the same position (like form the windows of a very tall building)
3. Take level pictures from the bottom.
4. Take level pictures from the top.
5. Compare, and determine margin of error based on your level and camera resolution to find statistical significance.

Your grasp of science and the notion of falsifiability is so poor, that if you had any shred of honesty at all you'd stop trying to use those words until you know what they mean.

[brimstoneSalad]

Stop editing more arguments into your posts after the thread has gone on for several more posts.

You didn't prove that the Earth is round, your statement is just a conjecture!

As mentioned above, you didn't understand what I said, and you don't understand what falsifiability is.
Do the tests yourself if you don't believe these things.
Nobody wants to waste time on you repeating experiments that have already proved the Earth round many times in many different ways.

I'm not trying to prove the Earth round, I'm explaining the round Earth model to you so that you can understand it, and how it accounts for all observations you are having trouble with.

Before we even began this conversation, I said clearly that was what I was going to do. I would show how the round Earth accounts for observations, and explain how the basic arguments against a round Earth are wrong (the Flat Earth arguments that claim to favor Flat Earth, and the ones which can be demonstrated wrong; not the infinitely unfalsifiable ones).
You have already broken your promise and started to create new unfalsifiable ad-hoc arguments for Flat Earth. I said I wouldn't chase this ever shifting goal post, you need to keep your promise.

Also, why don't you give me the numbers? Seriously, how can you calculate the angle at which you see the horizon assuming that the Earth is round?

Seriously? It's pretty basic trig. I feel like I'm explaining why 2+2=4
Fine. Give me a few minutes to draw a diagram and write you an equation.

[brimstoneSalad]

By the way, even flat-eathers understand that the horizon can be easily shifted around in camera frame depending on the angle:
http://www.theflatearthsociety.org/foru ... msg1529662

This is why it's essential to secure the camera angle.

This article explains how high the altitude needs to be to clearly see the curvature of the Earth:
https://www.osapublishing.org/ao/abstra ... -47-34-H39

Visual daytime observations show that the minimum altitude at which curvature of the horizon can be detected is at or slightly below 35,000  ft, providing that the field of view is wide (60°) and nearly cloud free.

Airplanes do go that high.
You need to understand optics much better than you do in order to understand why Flat Earther arguments are wrong. Like creationists, they appeal to science that's too difficult for stupid people to understand properly, so out of ignorance they dupe people.

[Jebus]

This discussion is quite interesting/entertaining as Teo has shown that flat earth theorists are not complete half wits. Usually the religious people I argue against have much worse grammar/debating skills.

So Teo, please satisfy my curiosity with the following:

If the earth is flat, why haven't any boats fallen off the edge? (or have they?)
How thick (deep) is the earth? Would any flat earth theorists argue a rectangular form (in case the thickness is significant)?
Does the bottom (or the sides) of the flat earth have any gravity? If so, are there any living beings there?
What would you estimate is the percentage of religious to non-religious flat earth believers?

Thanks. Looking forward to your reply.

[brimstoneSalad]

First, if you just weren't such an asshole maybe you would have just read and saved me trouble:
https://en.wikipedia.org/wiki/Horizon

If the very obvious diagrams and calculations on Wikipedia are inadequate for you, here's an even more obvious one:

diagramformoron1.gif

diagramformoron1.gif

(fixed)

The red lines indicate a standing man/or whatever you're standing on plus your height.

It should be visually clear from the different heights there that the angle becomes lower to the horizon as you get taller.

The radius of the Earth varies at different points, so this is only approximate and works best at sea level (which also varies based on tides), but it gets you close. You can use more specific numbers for elevation if you have them.

Looking for the angle, this is very basic trig which you said you understood (but that you probably lied about).

Hypotenuse = Radius + height (your height and whatever you're standing on)
Opposite = Radius
Adjacent = Distance to horizon (you could find this based on the others with A^2+B^2=C^2, but we don't need it for this calculation)

If you want the ideal (without any interference) angle below "eye level" that the horizon is at, then you want:

90° - arcsin(radius/(radius+height))

90° - arcsin(3,959 miles / (3,959 miles + 6 ft))

90° - 89.9565886°= 0.0434114°

Not very big when you're that short.

Climb a hundred feet, and it's a little bit more:

90° - arcsin(3,959 miles / (3,959 miles + 100 ft))
90° - 89.8227742° = 0.1772258°

With good equipment (a good camera, and careful leveling), you might be able to detect that.

Go higher: 2,717 ft tall Burj Khalifa in Dubai

90° - arcsin(3,959 miles / (3,959 miles + 2,717ft))

90° - 89.0762611° = 0.9237389°

That's almost a degree. A decent camera setup should easily detect that difference.

High airplane cruising altitude is even better, at 36,000 feet:

90° - arcsin(3,959 miles / (3,959 miles + 36,000ft))

90° - 86.6397796° = 3.3602204°

That starts to get more visually noticeable. If you were actually capable of leveling your eyes, that would be about 2.5% of your visual field and you'd probably notice it, it would look like this:

horizonshift.gif

horizonshift.gif

(fixed)
(Imagine that image fills your entire view, from top to bottom, and you can just barely see the edges of it. Or get really close to the screen.)

You're still really close to the ground at that point, but it gives you another sunset (as the sun has to 'lower' a bit more below the extended view and lower horizon).

There is some effect of refraction in the atmosphere, but it's a small difference: https://en.wikipedia.org/wiki/Horizon#E ... refraction

You can test and demonstrate this at home too. It shouldn't be big enough to need correcting for in such a simple experiment as going to a high floor on a building to see the horizon drop, but it adds a small margin of error you can adjust for it you want.

From orbit it's even better.
Although of course you're a moron and think satellites are a giant conspiracy theory (which would necessarily have hundreds of thousand of co-conspirators. Here's a list of satellites in GEO: https://en.wikipedia.org/wiki/List_of_s ... nous_orbit
Do you think all of the technicians are in on it? But whatever, conspiracy theories are unfalsifiable because their proponents are dishonest).
GEO orbit is 22,236 miles:

arcsin(3,959 miles / (3,959 miles + 22,236 miles))
90° - 8.69274851° = 81.30725149°

The Earth gets pretty tiny at that distance.

It's not something you'd notice with your eyes every day, not only because it's hard to pick up small changes from something stupid like climbing on your roof and thinking you'll see the curvature of the Earth, but because your eyes lock to the horizon and you use that to orient yourself. It's like using a compass to try to detect the error of a compass.

You need to use a level to get a controlled camera to shoot straight out, and do it over a much larger distance in altitude, and you need a high enough resolution (vertically) to be able to capture the difference.
There are also special range finding tools and telescopes with levels which would allow you to see how far the ground's horizon is below the astronomical horizon (directly out), but a camera with a good tripod and level should do the trick.

[brimstoneSalad]

This discussion is quite interesting/entertaining as Teo has shown that flat earth theorists are not complete half wits. Usually the religious people I argue against have much worse grammar/debating skills.

In terms of intellectual honesty, I think they're much worse. Religious people are just following what others believe. Flat Earthers have to actively deviate from convention into absurd beliefs. They work uphill against social norms in order to convince themselves of something so obviously wrong.

It's the equivalent difference of immoral behavior between a Texan who grew up with a BBQ family who eats meat because that's what everybody does, and a Hindu in some area of India where everybody is vegetarian and who grew up that way who decided to reject social norms and eat meat anyway -- it's about how much work you have to put in to do something immoral. Just because something is easy, that doesn't make it right. But when something wrong is harder to do and you do it anyway, it makes you much more of an asshole for putting in the hard work to do evil. That's Teo.

"If the earth is flat, why haven't any boats fallen off the edge? (or have they?)"

They think there's an ice wall around it guarded by arms guards.

"How thick (deep) is the earth? Would any flat earth theorists argue a rectangular form (in case the thickness is significant)?"

A substantial thickness would yield a gravitational pull toward the center. So, it has to be very thin. Like tissue paper thin.

Of course, Flat Earthers don't understand or believe in gravity, so they'll ignore that. That's one other proof the Earth isn't flat.

If you accept gravity, you'd have to accept that the earth is at least a rounded mound like a lens so that gravity from the center still pulls "down", but there are serious issues then with the acceleration model.

Nothing in physics makes sense if the Earth is flat seeing as they have to throw out one of the fundamental forces.

"Does the bottom (or the sides) of the flat earth have any gravity? If so, are there any living beings there?"

Flat Earthers mostly reject gravity. They believe that the disc of the Earth is accelerating through space creating the appearance of gravity.
This would require a god-like force. And also a very elaborate construction of exotic and probably physically impossible materials.

Most Flat Earthers are theists, so that's easy to understand. A Flat Earther who was an atheist would have to be a special kind of idiot.

"What would you estimate is the percentage of religious to non-religious flat earth believers?"

Hard to say. I can't find any very significant polls, but most have religious motivations.

http://rationalwiki.org/wiki/Flat_Earth

This article breaks some of them down.

[teo123]

OK, you are right, I didn't check the Wikipedia page about horizons and I should have. Admittedly, I was biased towards Flat Earthism. Hey, that was the first time I saw someone trying to use the perspective as an explanation. Our schools simply don't educate us well enough to understand why those types of explanations are faulty. I relied on my intuition instead of even trying to calculate how far the horizon would drop down and I simply couldn't imagine how big the Earth is.
But I don't think you should blame me for everything. Look, Wikipedia doesn't even mention that there is an angle at which you see the horizon. As for the Mount Everest, the professional photographers use special braces to ensure the camera is correctly aligned, right? So, you asked me to try that at home, yet it is not visible even from the Mount Everest. Lot of people believe that the Earth looks round from there, when it simply doesn't. The horizon isn't even visible from the Mount Everest. So, I assumed that you also believe that. As for the airplanes, I considered that also. I assumed it is impossible to correctly align a camera on an airplane since it doesn't move neither at a constant speed (so you would have to deal with inertial forces) neither at a constant angle (so it is not helpful to use braces). Am I wrong?

[brimstoneSalad]

OK, you are right, I didn't check the Wikipedia page about horizons and I should have. Admittedly, I was biased towards Flat Earthism.

Thank you for admitting that.

Hey, that was the first time I saw someone trying to use the perspective as an explanation.

That's the standard explanation. On the Flat Earth forums, most people are more interested in proving Flat Earth wrong than demonstrating why Round Earth is consistent -- this is a problem.
As I explained before we began this, it's impossible to prove Flat Earth wrong because it's a conspiracy theory and an ad-hoc hypothesis with ever moving goal posts, just as most people can't prove that God does not exist because it's purportedly unfalsifiable -- as soon as I debunk one argument, a new model/excuse can be made which overcomes those problems.

This is why my point here is just to explain how the Round Earth works, and show you how it fits our observations.
And, crucially, how science works and why we should always prefer the falsifiable model which makes real predictions and is a genuine theory to an ad-hoc hypothesis which fails to make predictions and constantly changes when confronted with evidence against it when it does.

This is an issue of intellectual honesty, and why legitimate science is special, and superior to religion and other pseudosciences.

Round Earth is completely consistent with observation. That's all we need to know in order to accept it for now -- we TENTATIVELY accept scientific findings until we have the means to demonstrate otherwise. You do not have those means, and nobody on the Flat Earth forums does either.
Anybody with those means -- a basic education in math and physics -- can work out simple tests at home to prove it.

Our schools simply don't educate us well enough to understand why those types of explanations are faulty. I relied on my intuition instead of even trying to calculate how far the horizon would drop down and I simply couldn't imagine how big the Earth is.

Intuition -- not just your intuition, but all intuition -- is unreliable and very often wrong, particularly at scales and using concepts that are unrelated to primitive human behavior. If it's not relevant to a cave man's survival, your intuition about it is probably wrong.

Read this: http://hubpages.com/education/Counterin ... Statistics

NEVER make 'intuitive' assumptions when it comes to math or statistics. Your brain is not built for it.
If you don't explicitly do the math (and check it), do not trust yourself.

The most important thing you can learn about science is to discard your intuitions and control your biases; this is the only way we access a shared and objective reality.

But I don't think you should blame me for everything. Look, Wikipedia doesn't even mention that there is an angle at which you see the horizon.

It's something that should be self evident based on the trigonometry. You can see by my diagram, I hope, that the angle the tall man is viewing the horizon at is lower.

As for the Mount Everest, the professional photographers use special braces to ensure the camera is correctly aligned, right?

No, they use a tripod to keep the camera from moving. They are not trying to center anything, they're just artists (photographers are not scientists, they frame things however they think they will look good, and then crop them more later).

Anyway, the Mount Everest is a bad example, because you can not see the sea level horizon, you can just see mountains.
You need to view the same level horizon from low and high up to see the change. If the horizon you're looking at is elevated too, that's a different situation.

So, you asked me to try that at home, yet it is not visible even from the Mount Everest.

The mountain picture is a bad example. Not only is it not a level shot, the horizon being viewed is mountains, which are not significantly shorter than the mountain from which the picture is taken. You need a large height difference between yourself and the horizon.

Can you find a tall building near you from which you can see the ocean, or a very level plane on the horizon?

Lot of people believe that the Earth looks round from there, when it simply doesn't.

Lots of vegans make the argument that we shouldn't eat meat because there's magical fear essence in the food which causes us to become spiritually violent.
This isn't a good argument. Does that make veganism wrong? Of course not. That's just a bad argument for it.

I'm sure there are plenty of mathematically and scientifically illiterate members of the Flat Earth forum who have made bad arguments for the Earth being round.

The sea-level horizon, IF you could see it all around Mt. Everest, would be ever so slightly curved, but the curve would not likely be enough for you to see with your eye. You'd need to use special equipment to detect it.

Did you read that abstract I linked you to, which was from a study about the minimum altitude at which a photograph would be able to clearly show the curvature of the Earth?
https://www.osapublishing.org/ao/abstra ... -47-34-H39
35,000 feet.
Everest is only 29,000 feet above sea level -- this may not be enough -- AND the land around it is higher than sea level, so the horizon is raised too because it is elevated on other mountains.
You need to be up high, AND have a clear view of a low altitude horizon.
Everest satisfies neither of these criteria. We would not expect to be able to visually discern the curvature of the Earth from such a low vantage point, surrounded by such high elevated (and irregular) land.

Don't assume I'm making a particular argument without asking. We could calculate the curvature expected from a particular elevation (that study only examined one, it looks like), but the math would be too much for you, and I'm not interested in spending hours drawing diagrams to explain it.

As for the airplanes, I considered that also. I assumed it is impossible to correctly align a camera on an airplane since it doesn't move neither at a constant speed (so you would have to deal with inertial forces) neither at a constant angle (so it is not helpful to use braces). Am I wrong?

It's not difficult to align a camera on an airplane. You need something like gyroscopic stabilization.
https://www.youtube.com/watch?v=2BSY_0md_sY
Airplanes move at a pretty constant speed once at altitude, as long as they are not in turbulence.

However, you don't need an airplane. A tall enough building should be suitable.
OR you can just learn more about astronomy and geophysics, and realize that at least millions of people would have to be in on the conspiracy to cover up the Earth being flat.

What you have been experiencing is something called the Dunning-Kruger effect:
https://en.wikipedia.org/wiki/Dunning%E ... ger_effect

Your knowledge of science and mathematics is so minuscule, you do not yet know enough to understand how much you do not know. It would (and will if you study) blow your mind.

I could prove the Earth is round with a good clock (probably a real atomic clock, which would be a little expensive but still affordable to the average person).
Did you know that time is slower in a gravity well, and that a clock ticks a little slower closer to the Earth than high up?
This would not occur if the Earth were in a constant force field of acceleration, and only works with a round Earth and gravity.
This all comes from relativity, which is the cornerstone of modern physics (E=mc^2).
This has been proved many times across the world: http://www.dailymail.co.uk/sciencetech/ ... itude.html

I could prove the Earth is round with a carefully prepared tank of water.
Did you know the rotation of the Earth means there is a slight circular force applied to everything, and is different in the North and South hemispheres?
This could not occur on a flat Earth.
This all comes from basic Newtonian physics.
https://en.wikipedia.org/wiki/Coriolis_ ... nd_toilets
It's a misconception that toilets/sinks/etc. drain in a particular direction because of this (this has to do with jet direction, shape of the tub, or movement in the water from being disturbed), but you can prepare a still sample of water and observe the effect.

I could probably list out a dozen experiments you could do at home and with minimal monetary investment which would all prove the Earth is round. I've probably already blown your mind with those two examples (which are relatively trivial).
The thing is that you don't even have the basic scientific literacy to understand how the Earth can be proved round, and how much of science relies on these observations.
You have failed to understand how EVERYTHING in science would be wrong if the Earth was flat. I would probably be worshiping its makers, since such a flat construction obviously could not arise naturally.

There's no reason for you to do any of these experiments yourself, because the very idea that you would doubt this only reveals an ignorance of science too profound to pull off any of these experiments.

Other people know more than you do. It's pretty simple, and once you grasp that concept and stop insulting everybody who has scientific literacy basic enough to understand why the Earth is round and that the Flat Earth model is pseudoscience, you'll be equipped to start really learning about the world around you instead of these masturbatory fantasies.

Do you have any other reservations about the Round Earth model?

[teo123]

I must admit that knowing about the horizons really makes me far less confident that the Earth is flat.
Actually, I did most of what you just posted. Mostly from the Flat Earth Theory. They have made a ad-hoc to explain that away. The apparent curvature of the horizon from high-altitude photographs is explained by the Sun. They claim that the apparent horizon is places from where you currently see the sunset. And that you can't see any farther because the exposure of the camera is not long enough. Motivated by this conversation, I tried to calculate the angle at which you should see the Polaris at the equator right above the atmosphere. Well, assuming that the Polaris is 5000 kilometers right above the north pole and the equator is 10000 kilometers from the north pole, that should be atan(5000/10000)=27 degrees. Well, since the Polaris is visible right at the horizon from the equator, you should expect most of the stars to be tight in that angle. Yet you don't see a bright line at your eye level on those photographs. They even claim it is the only right explanation because the horizon seems elliptical and not circular (I don't see any logic in it, though). I've also tried to draw a diagram to see whether the refractions or reflections up in the atmosphere are explanations for that unknown phenomena, and, you were right, they are not. As for the atomic clocks, they explain this by the stars having small gravitational field (and that should have exactly the opposite effect, right?). For the coriolis, they explain this away as the shadow of aetheric wind, since they claim it can only be observed up in the atmosphere (of course, they don't give any explanation for what an aether even is).
But, yes, of course I have questions about the Round Earth Theory. So, you claimed that the Earth being flat wouldn't explain the bottoms of the ships reappearing when zooming the camera. Well, they have an explanation how it could. I've bothered to draw a diagram based on it. What's wrong with it?

Also, how do you explain the fact that the Moon doesn't appear to get its light from the Sun?

[teo123]

Sorry, here is a correct URL of that diagram.