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Very Wrong Math

charlespetzold.com

61–70 of 109 posts

Re: Very Wrong Math

#61
post #51

Earlier quoted context omitted.

They mean it is actually accelerating constantly. My math might be wrong, but if we were accelerating at 9.8m/s/s for at least 4000 years (roughly as long as we have continuously recorded history and the minimum time “gravity” has been observed) then we ought to currently be traveling through space at over 1,000,000,000,000m/s. Now I’m no physicist, but I reckon that might end up violating causality.

Nah, when you move that fast, further acceleration stops increasing speed and starts squishing time instead, so you asymptotically approach C. So I guess what I'm saying is I see absolutely no problem with the flat earth arguments?

wait, is the flat earth theory going to make me immortal?

Re: Very Wrong Math

#62

Earlier quoted context omitted.

Nah, when you move that fast, further acceleration stops increasing speed and starts squishing time instead, so you asymptotically approach C. So I guess what I'm saying is I see absolutely no problem with the flat earth arguments?

wait, is the flat earth theory going to make me immortal?

Only if you truly believe in it. Then you create a belive field, shaping your reality in any form you desire.

Re: Very Wrong Math

#63

I have seen a very similar (incorrect) argument used to justify the idea of a flat earth. A builder on youtube made the argument (with a similar out of scale drawing of the earth) that if he drops a plumb bob and makes a right angle so he has a straight horizontal line and then goes across that line for a bit and drops another plumb bob, the two lines he has dropped are parallel, "proving" that the surface of the ear…

Ah, but would they actually be parallel on a flat earth? Say the earth is disc-shaped. Then the center of gravity is only directly beneath you if you're standing at the exact center. You get ever-so-slightly not parallel lines, just like on a round earth. The fun part of a disc-shaped earth comes as you move towards the sides, and gravity, still pointing towards the center, makes you stand at an increasingly acute an…

Doesn't the flat earth extend infinitely in all directions?

Re: Very Wrong Math

#64
post #46
post #37

One question I've always had with this: How does the rotation of the earth affect an airplane's flight time, if any? And how does this change with altitude?

Simple answer: Zero. Because the planes move inside the atmosphere, which moves with the earth. A more nuisance would be that earth rotating generate all sorts of things in the atmosphere, including winds and Coriolis effect on the winds, and you can account for that considering the winds. Btw a flight from Chile to France and back, will have a leg significantly shorter (up to 2 hs in a 13hs flight) and which leg it…

Interesting to know about the Coriolis effect.

I get that what really matters is the relative motion, but it still seems to me that there might be a gravitational/inertial effects at play, even if tiny.

Consider this thought experiment: Planes cannot really fly into space, but assume they can. At a certain altitude, it cannot be said the the plane is moving perfectly in step with the gravity of the earth. At infinite altitude, that certainly cannot be the case.

So that tells me there is some deviation due to the inertia of the plane, even at low altitudes. Like I said, the effect might be tiny, but would be interesting to learn more about it nonetheless.

Re: Very Wrong Math

#65

Earlier quoted context omitted.

For convenience, we set τ=2pi. :-) x = τ(r+1) - τr = τ(r+1-r) = τ(1) = τ

How do you pronounce that symbol?

https://doc.rust-lang.org/stable/std/f64/consts/constant.TAU...

https://docs.python.org/3/library/math.html#math.tau

https://www.google.com/search?q=tau*1

https://docs.oracle.com/en/java/javase/21/docs/api/java.base...

https://learn.microsoft.com/en-us/dotnet/api/system.math.tau...

Re: Very Wrong Math

#66
post #37

One question I've always had with this: How does the rotation of the earth affect an airplane's flight time, if any? And how does this change with altitude?

It does not really, at least not directly. What matters is relative velocity compared to the starting and final locations, and relative to the air around the aircraft. It just happens that there are very powerful atmospheric currents that go west to east (those are due to the earth’s rotation, among others phenomena). So, when flying towards the east, catching these currents can significantly reduce flying time. When…

Thanks for this explanation; quite interesting.

But it still seems to me that there might be a gravitational/inertial effects at play as well. At a (hypothetical) infinite altitude, it can no longer be said the the plane is moving perfectly in lock-step with the gravity/rotational acceleration of the earth. This implies the inertia of the plane relative to the rotation of the earth still has an effect at lower altitudes.

The effect might be tiny, but would be interesting to learn more about it nonetheless.

Re: Very Wrong Math

#67
post #64
post #46

Earlier quoted context omitted.

Simple answer: Zero. Because the planes move inside the atmosphere, which moves with the earth. A more nuisance would be that earth rotating generate all sorts of things in the atmosphere, including winds and Coriolis effect on the winds, and you can account for that considering the winds. Btw a flight from Chile to France and back, will have a leg significantly shorter (up to 2 hs in a 13hs flight) and which leg it…

Interesting to know about the Coriolis effect. I get that what really matters is the relative motion, but it still seems to me that there might be a gravitational/inertial effects at play, even if tiny. Consider this thought experiment: Planes cannot really fly into space, but assume they can. At a certain altitude, it cannot be said the the plane is moving perfectly in step with the gravity of the earth. At infinite…

I meant coriolis effect on the wind. Not sure if noticeable in a plane.

Re: Very Wrong Math

#68

I have seen a very similar (incorrect) argument used to justify the idea of a flat earth. A builder on youtube made the argument (with a similar out of scale drawing of the earth) that if he drops a plumb bob and makes a right angle so he has a straight horizontal line and then goes across that line for a bit and drops another plumb bob, the two lines he has dropped are parallel, "proving" that the surface of the ear…

Ah, but would they actually be parallel on a flat earth? Say the earth is disc-shaped. Then the center of gravity is only directly beneath you if you're standing at the exact center. You get ever-so-slightly not parallel lines, just like on a round earth. The fun part of a disc-shaped earth comes as you move towards the sides, and gravity, still pointing towards the center, makes you stand at an increasingly acute an…

Even physicists have a hard time with disks and gravity. I can't tell you how many times I've seen them use the shell theorem on galaxies (does not apply). The only dark matter is in their head ;-)

Re: Very Wrong Math

#69
post #28

Earlier quoted context omitted.

Ah, but would they actually be parallel on a flat earth? Say the earth is disc-shaped. Then the center of gravity is only directly beneath you if you're standing at the exact center. You get ever-so-slightly not parallel lines, just like on a round earth. The fun part of a disc-shaped earth comes as you move towards the sides, and gravity, still pointing towards the center, makes you stand at an increasingly acute an…

Standard flat-earther response is to scornfully deny the existence of gravity. It's all density/buoyancy you see... Gravity is a hoax promulgated by the notorious cabalist Newton, in service to his Illuminati/Papal masters, etc, etc.

Why do we still talk about these people? The more we stand in awe of their calculated ignorance, the more satisfied they are.

I feel like there are better things to do with my time than be as fascinated by it as some people.

Re: Very Wrong Math

#70
post #51

Earlier quoted context omitted.

They mean it is actually accelerating constantly. My math might be wrong, but if we were accelerating at 9.8m/s/s for at least 4000 years (roughly as long as we have continuously recorded history and the minimum time “gravity” has been observed) then we ought to currently be traveling through space at over 1,000,000,000,000m/s. Now I’m no physicist, but I reckon that might end up violating causality.

Nah, when you move that fast, further acceleration stops increasing speed and starts squishing time instead, so you asymptotically approach C. So I guess what I'm saying is I see absolutely no problem with the flat earth arguments?

Can’t argue with that, I guess.
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