[Boots]

I know this has been discussed and I did look up a few threads on it, but I would still like to start a new topic about a specific question I have.

If the speed of light is 299792458 m/s and we assume an acceleration rate of 9.8m/s², then we should be able to divide (299792458/9.8 )  to come to the conclusion that we will be travelling at the speed of light in 30591067 seconds. Or around 354 days. If this is not the case, I would be very happy if someone would take the time to explain to me what the velocity of the earth would be in m/s after 354 days?

[rabinoz]

I know this has been discussed and I did look up a few threads on it, but I would still like to start a new topic about a specific question I have.

If the speed of light is 299792458 m/s and we assume an acceleration rate of 9.8m/s², then we should be able to divide (299792458/9.8 )  to come to the conclusion that we will be travelling at the speed of light in 30591067 seconds. Or around 354 days. If this is not the case, I would be very happy if someone would take the time to explain to me what the velocity of the earth would be in m/s after 354 days?

I do not for one minute accept that gravity is caused by "Universal Acceleration", but even Einstein's Special Relativity would limit the velocity to "c".

The earth would appear to earth bound observers to be continually accelerating at 9.8m/s², but on earth we would have no way of knowing our velocity.
To flat earth dwellers, light would still travel at 299,792,458 m/s, but to an observer in an "inertial reference frame" (that is someone not accelerating) the velocity of earth would appear to approach the speed of light asymptotically.

I have tried to calculate how close the velocity of earth would be to the velocity of light, but any calculation I have tried runs into overflow after a couple of centuries.

There are other implications, but I won't dwell on them now.

[Boots]

I know this has been discussed and I did look up a few threads on it, but I would still like to start a new topic about a specific question I have.

If the speed of light is 299792458 m/s and we assume an acceleration rate of 9.8m/s², then we should be able to divide (299792458/9.8 )  to come to the conclusion that we will be travelling at the speed of light in 30591067 seconds. Or around 354 days. If this is not the case, I would be very happy if someone would take the time to explain to me what the velocity of the earth would be in m/s after 354 days?

I do not for one minute accept that gravity is caused by "Universal Acceleration", but even Einstein's Special Relativity would limit the velocity to "c".

The earth would appear to earth bound observers to be continually accelerating at 9.8m/s², but on earth we would have no way of knowing our velocity.
To flat earth dwellers, light would still travel at 299,792,458 m/s, but to an observer in an "inertial reference frame" (that is someone not accelerating) the velocity of earth would appear to approach the speed of light asymptotically.

I have tried to calculate how close the velocity of earth would be to the velocity of light, but any calculation I have tried runs into overflow after a couple of centuries.

There are other implications, but I won't dwell on them now.

Thanks for the response. I would like to understand Einstein's theory of relativity better. Asking these questions is helping me to understand it better. (I think/hope.)

But the way I see it now, if the speed of light is some finite distance per unit of time, and the earth is infinitely accelerating, it seems inevitable that at some point the speed of light will be exceeded. (Infinity > x  where x is a finite number)For sure from the perspective of a fixed position in space. I too believe that the velocity would be limited to c. Which is why it does not seem to me that infinite acceleration is possible. At any rate, if that was the case, I guess the sun moon and stars would also be infinitely accelerating in the same direction or we would soon leave them in the space dust.

Also, doesn't this just create a bigger problem? What is causing this acceleration? it seems like it would be something as hard or harder to believe than the theory of gravity.

[rabinoz]

Thanks for the response. I would like to understand Einstein's theory of relativity better. Asking these questions is helping me to understand it better. (I think/hope.)

But the way I see it now, if the speed of light is some finite distance per unit of time, and the earth is infinitely accelerating, it seems inevitable that at some point the speed of light will be exceeded. (Infinity > x  where x is a finite number)For sure from the perspective of a fixed position in space. I too believe that the velocity would be limited to c. Which is why it does not seem to me that infinite acceleration is possible. At any rate, if that was the case, I guess the sun moon and stars would also be infinitely accelerating in the same direction or we would soon leave them in the space dust.

Also, doesn't this just create a bigger problem? What is causing this acceleration? it seems like it would be something as hard or harder to believe than the theory of gravity.

I'll answer the last part first. You ask
"Also, doesn't this just create a bigger problem? What is causing this acceleration? it seems like it would be something as hard or harder to believe than the theory of gravity."
                 About all I can say is, in my humble opinion, yes, "dark energy", whatever that is and yes, I find gravity much easier to believe.
But (there's always a but) gravity caused by a finite diameter (24,900 miles) flat earth would point down in the centre (their North pole), but as the edge was approached it would start to point not quite down, but have component pointing in towards the centre as well. On earth gravity is always down, at right angles to to the surface.

So flat earthers have to deny gravity, even though in my opinion it is well supported by evidence and measurements. So, Newton, Cavendish and others often get demonised.

As to explaining relativity, it's a big topic.

The need for something like relativity probably arise with James Clerk Maxwell's claim that the electromagnetic properties of "space" were independent of location and (uniform) velocity.

Since the velocity of light (electromagnetic radiation) is determined by these properties (magnetic permeability and electrostatic permittivity), the velocity of light must be the same for any observer, no matter what their  (uniform) velocity.

Rather than makin a long post I will give a few references. See what you make of them.
Special Relativity Simplified
SPECIAL RELATIVITY EXPLAINED BY THOUGHT EXPERIMENTS
Special relativity.
There is also this video, I have no idea what it is like, here's hoping it helps

Best of luck! Then there's General Relativity, but that's a whole new ballgame.

[Southernhemispere]

You will find that FE'ers don't believe in Einstein's theories, but will use part of his works where it suits them; they will not believe in dark matter, but then could use it as part of the theory on how the earth accelerates;  don't believe in satellites and Google maps, but use them to illustrate lens distortion and distances between places on earth; so I leave the conclusion to your judgement.
We cannot reach the speed of light , but we cannot slow the acceleration or people would start becoming weightless, but at least they haven't thought of the solution that the flat earth is in the gravitational orbit of a central God's 'planet', at a constant orbital acceleration of 9.8 mps. Oops, maybe someone will now use this!

[Boots]

Thanks for the response. I would like to understand Einstein's theory of relativity better. Asking these questions is helping me to understand it better. (I think/hope.)

But the way I see it now, if the speed of light is some finite distance per unit of time, and the earth is infinitely accelerating, it seems inevitable that at some point the speed of light will be exceeded. (Infinity > x  where x is a finite number)For sure from the perspective of a fixed position in space. I too believe that the velocity would be limited to c. Which is why it does not seem to me that infinite acceleration is possible. At any rate, if that was the case, I guess the sun moon and stars would also be infinitely accelerating in the same direction or we would soon leave them in the space dust.

Also, doesn't this just create a bigger problem? What is causing this acceleration? it seems like it would be something as hard or harder to believe than the theory of gravity.

I'll answer the last part first. You ask
"Also, doesn't this just create a bigger problem? What is causing this acceleration? it seems like it would be something as hard or harder to believe than the theory of gravity."
                 About all I can say is, in my humble opinion, yes, "dark energy", whatever that is and yes, I find gravity much easier to believe.
But (there's always a but) gravity caused by a finite diameter (24,900 miles) flat earth would point down in the centre (their North pole), but as the edge was approached it would start to point not quite down, but have component pointing in towards the centre as well. On earth gravity is always down, at right angles to to the surface.

So flat earthers have to deny gravity, even though in my opinion it is well supported by evidence and measurements. So, Newton, Cavendish and others often get demonised.

As to explaining relativity, it's a big topic.

The need for something like relativity probably arise with James Clerk Maxwell's claim that the electromagnetic properties of "space" were independent of location and (uniform) velocity.

Since the velocity of light (electromagnetic radiation) is determined by these properties (magnetic permeability and electrostatic permittivity), the velocity of light must be the same for any observer, no matter what their  (uniform) velocity.

Rather than makin a long post I will give a few references. See what you make of them.
Special Relativity Simplified
SPECIAL RELATIVITY EXPLAINED BY THOUGHT EXPERIMENTS
Special relativity.
There is also this video, I have no idea what it is like, here's hoping it helps

Best of luck! Then there's General Relativity, but that's a whole new ballgame.

Thanks. That was interesting. It is a big topic but in a nutshell, we wouldn't be able to exceed the speed of light because as we approached the speed of light time would slow down? This leads to the conclusion that if the earth is accelerating infinitely, then time must be running slower and slower, relative to that part of the universe that is not accelerating with us.

[Boots]

You will find that FE'ers don't believe in Einstein's theories, but will use part of his works where it suits them; they will not believe in dark matter, but then could use it as part of the theory on how the earth accelerates;  don't believe in satellites and Google maps, but use them to illustrate lens distortion and distances between places on earth; so I leave the conclusion to your judgement.
We cannot reach the speed of light , but we cannot slow the acceleration or people would start becoming weightless, but at least they haven't thought of the solution that the flat earth is in the gravitational orbit of a central God's 'planet', at a constant orbital acceleration of 9.8 mps. Oops, maybe someone will now use this!

Yes. A similar thought has been going through my mind. Isn't the flat earth philosophy to take no ones word for it and believe only what one can see with one's own eyes. The theory of special relativity and "dark energy" seem like fairly complicated concepts. I think most people, FE and GE alike are just taking Einstein's and the scientific community's word for it when it come to his theories of relativity.

[rabinoz]

Thanks. That was interesting. It is a big topic but in a nutshell, we wouldn't be able to exceed the speed of light because as we approached the speed of light time would slow down? This leads to the conclusion that if the earth is accelerating infinitely, then time must be running slower and slower, relative to that part of the universe that is not accelerating with us.

I quite agree with your conclusion. You seem to be catching on to relativity pretty quickly. At lot of people ridicule it, yet it is ultimately based on of the properties of "space" not varying with constant velocity and thus idea goes back to Galileo, not that he knew anything much about electricity.

But I cannot get any Flat Earthed to take thus "time dilation", as it is called, seriously. The nearest to an answer is the claim that there is not proof that there is a "part of the universe that is not accelerating with us".

I like to claim that this proves that this flat earth must be 42 years old (and you will realise the significance of 42 if you have read or seen "The Hitchhiker's Guide to the Galaxy", a comedy science fiction series created by Douglas Adams). My 42 years is just as fictitious as "The Hitchhiker's Guide", by the way.

I made a post on this topic in Flat Earth Q&A / Re: gravity « Message by rabinoz on April 09, 2016, 02:17:43 AM »

In that post I claimed that if the "universe not accelerating" began "13.8 billion years ago, . . . . . . . . . . due to time slowing down on the accelerating earth (that is Time Dilation) only 45.3 years would have elapsed on our earth" So it was 45.3 years I claimed as the maximum age of the flat earth, and not actually 42, but near enough.

It was all a bit "tongue in cheek" of course, but meant to point out what I think is a massive flaw in the idea of Universal Acceleration.

[Boots]

But I cannot get any Flat Earthed to take thus "time dilation", as it is called, seriously. The nearest to an answer is the claim that there is not proof that there is a "part of the universe that is not accelerating with us".

This is hard to comprehend. What about the space we are supposedly accelerating through? If it is accelerating with us than how can we be accelerating through it?

I like to claim that this proves that this flat earth must be 42 years old (and you will realise the significance of 42 if you have read or seen "The Hitchhiker's Guide to the Galaxy", a comedy science fiction series created by Douglas Adams). My 42 years is just as fictitious as "The Hitchhiker's Guide", by the way.

I made a post on this topic in Flat Earth Q&A / Re: gravity « Message by rabinoz on April 09, 2016, 02:17:43 AM »

I read it. LOL. In that thread I read something else that puzzled me:

Q: Why does gravity vary with altitude?
A: The moon and stars have a slight gravitational pull.

What? I thought the whole point was that the idea of bodies of mass attracting each other through the vacuum of space was absurd.

[rabinoz]

I read it. LOL. In that thread I read something else that puzzled me:

Q: Why does gravity vary with altitude?
A: The moon and stars have a slight gravitational pull.

What? I thought the whole point was that the idea of bodies of mass attracting each other through the vacuum of space was absurd.

Yes, a lot do think that "was that the idea of bodies of mass attracting each other through the vacuum of space was absurd".

But many do consider that there is "Celestial Gravitation" as in

Celestial Gravitation
Celestial Gravitation is a part of some Flat Earth models which involve an attraction by all objects of mass on earth to the heavenly bodies. This is not the same as Gravity, since Celestial Gravitation does not imply an attraction between objects of mass on Earth. Celestial Gravitation accounts for tides and other gravimetric anomalies across the Earth's plane.

You can look up "the Wiki" from the "Wiki" link on TFES home page The Flat Earth Society.

What seems quite inconsistent to me in this is the statement "Celestial Gravitation does not imply an attraction between objects of mass on Earth",
then the assertion that "Celestial Gravitation accounts for tides and other gravimetric anomalies across the Earth's plane".

I would have thought mass is well mass  ! But, I'm not the one to ask on "Flat Earth" inconsistencies!

You might find many "explanations" in "the Wiki" quite entertaining!, try:

Magnification of the Sun at Sunset
Q: If the sun is disappearing to perspective, shouldn't it get smaller as it recedes?
A: The sun remains the same size as it recedes into the distance due to a known magnification effect caused by the intense rays of light passing through the strata of the atmolayer.

A "known magnification effect"? I started a thread on the sun staying exactly the size (within measurement errors) all through the day in:
The Constancy of the Angular size of the Sun « on: August 24, 2016, 08:12:47 PM » - note that this is on "the other Flat Earth Society" at
The Flat Earth Society - you would find that Society "quite different!"

and a post on the moon being almost the same size in the sky.
Re: Flat Earth Proof, popular astronomy debunk: Sun Changes Size « Reply #8 on: June 28, 2016, 03:56:31 AM »)

No-one bothers much!

Also try to explain this:

The Lunar Eclipse
A Lunar Eclipse occurs about twice a year when a satellite of the sun passes between the sun and moon.
This satellite is called the Shadow Object. Its orbital plane is tilted at an angle of about 5°10' to the sun's orbital plane, making eclipses possible only when the three bodies (Sun, Object, and Moon) are aligned and when the moon is crossing the sun's orbital plane (at a point called the node). Within a given year, considering the orbitals of these celestial bodies, a maximum of three lunar eclipses can occur.
. . . . . . . . . . . . . . .
It is estimated that the Shadow Object is around five to ten miles in diameter. Since it is somewhat close to the sun the manifestation of its penumbra upon the moon appears as a magnified projection. This is similar to how during a shadow puppet show your hand's shadow can make a large magnified projection upon your bedroom wall as you move it closer to the flashlight.

I have never managed to work out how this "five to ten miles in diameter" "Shadow Object" could possibly stop all the light from a 32 mile diameter sun from reaching a 32 mile diameter moon.

[Rounder]

It doesn't block ALL the light, just enough to cast a penumbral shadow.

[rabinoz]

It doesn't block ALL the light, just enough to cast a penumbral shadow.

I hate to "object", but during a total lunar eclipse the moon enters the umbra of the earth's shadow, as in

Geometry of a Lunar Eclipse

-------

Total lunar eclipse September 28, 2015

Both from: Wikipedia, Lunar eclipse

In the umbra the body of the earth blocks all the sunlight from the moon, but some light is refracted by the atmosphere to faintly illuminate the moon. This light is a reddish colour because Rayleigh scattering filters out most of the shorter wavelengths (the green and blue) leaving mainly the reds.

The difference might be be a bit subtle, but if the earth had no atmosphere, during a total lunar eclipse the moon would be in near enough to total darkness, with the only illumination being from starlight.

On the Flat Earth model, the tiny shadow object would not be able to cast even a significant penumbra.

[Boots]

note that this is on "the other Flat Earth Society" at
The Flat Earth Society - you would find that Society "quite different!"

I tried to sign up but the sign up icon just links to the forum index page.

[Rounder]

My mistake, Rabinoz, I should have remembered that!

[truth]

Gravity is caused by the acceleration downwards and the movement of the earth from concave to flat to convex.