[xenotolerance]

One of theoretical physics' top questions is indeed, What causes gravity? Ask Rovelli:

According to Einstein, gravity is not a force – it is a property of space-time itself. Loop quantum gravity is an attempt to develop a quantum theory of gravity based directly on Einstein's geometrical formulation.

One way to put it is that gravity does not need energy because it is energy, but the only thing it can do is move things from high altitudes to low altitudes. In these terms, it is also known as potential energy. But I do recommend studying loop quantum gravity, because it rules pretty hard, although it is predicated on general relativity and quantum physics with which flat earth does not play well.

Speaking of which - finite acceleration within one reference frame can never reach the speed of light, something that is brought up early and often by universal accelerator proponents when people raise that objection. However, this limit is famously part of special relativity which, being based on Newton's theory of gravity, obviates the universal accelerator idea completely. Relativity replaces Newton's theory by, in brief, combining certain variables, but it doesn't eschew gravity at all.

[juner]

Ah - that game my 5 year old granddaughter plays...they ask a question, you answer, they say "Why?" so you explain and they say "Why?" so you explain that and then they say "Why?" again.

Funny, there wasn't an explanation for the question I asked at all. I would suggest you go back and read the thread again to clear up your apparent misunderstanding, then maybe try again.

Ultimately, we know what mass does - it makes gravity.  And that's because of the curvature of space-time and...well, I guess we ran out of answers for "Why?".

You could have just said you don't know to begin with. Nothing wrong with that. Although mass and energy tend to have a bit of an equivalence, especially in relativity. Of course, you already know this.

But unless I'm very much mistaken, FET has gravity too...

Nope.

But NOWHERE do we get free energy - we even have one of the best established laws of physics that says "No Free Energy!!"

Correct. Again, it is almost like there is an equivalence somewhere in there.

If Earth is accelerating up at 9.8 m/s/s that means in 24 hours Earth would have accelerated by:
60s/min x 60 min/hr x 24hr/day x 9.8 m/s/s = 846,720 m/s/s per day.
Which means within 360 days the earth would have accelerated by 846,720 x 360 = 304,819,200 m/s/s.
Which means each year Earth would have accelerated beyond the speed of light. Relativity tells us this is impossible so what is the solution to this dilemma? Alternatively what is the source of energy driving the continued acceleration of Earth?

Special relativity is your solution. I would suggest looking into it and you will find that you can undergo constant acceleration and asymptotically approach the speed of light, but never reach it.

[3DGeek]

If Earth is accelerating up at 9.8 m/s/s that means in 24 hours Earth would have accelerated by:
60s/min x 60 min/hr x 24hr/day x 9.8 m/s/s = 846,720 m/s/s per day.
Which means within 360 days the earth would have accelerated by 846,720 x 360 = 304,819,200 m/s/s.
Which means each year Earth would have accelerated beyond the speed of light. Relativity tells us this is impossible so what is the solution to this dilemma? Alternatively what is the source of energy driving the continued acceleration of Earth?

Argh...STOP SAYING THAT!  You clearly don't understand relativity.

That is NOT the problem here.   Relativity says that from the perspective of people here on Earth, we can indeed keep accelerating indefinitely.   From the perspective of some hypothetical "stationary" being off to the side, watching this happen, they'd see the clocks of people here slowing down more and more (because of time dilation) and the length of the earth (and our rulers) stretching out further and further in the direction the Earth is travelling - so that the Earth would indeed never exceed light speed.

There are plenty of OTHER problems with FET - but modern physics says that this isn't one of them!

[Curious Squirrel]

But unless I'm very much mistaken, FET has gravity too...

Nope.

Until you actually explain the difference between gravity and gravitation, yes, yes you do. So far you have not other than to simply claim the last thread it came up in already explained it.

I would also note the infinite Earth plane does feature gravity, although it's not the preferred model on THIS site, it is on the other one. Just a note for others.

[Ga_x2]

But unless I'm very much mistaken, FET has gravity too...

Nope.

I understand you're the ultimate master in hair splitting, but it really makes no sense in this context. Gravity / gravitation, tomato / tomahto, it remains an unexplained mess, that you should clear up beyond a one-liner in the wiki.
I also keep bringing up the Cavendish experiment, in this regard, but I only get crickets in response  (beside a random link from Tom that amused me for days). I understand that bumping threads is not kosher, so if anyone has an answer, it'd be super nice if they'd fish the question a few pages back and have at it.
Besos

[StinkyOne]

If Earth is accelerating up at 9.8 m/s/s that means in 24 hours Earth would have accelerated by:
60s/min x 60 min/hr x 24hr/day x 9.8 m/s/s = 846,720 m/s/s per day.
Which means within 360 days the earth would have accelerated by 846,720 x 360 = 304,819,200 m/s/s.
Which means each year Earth would have accelerated beyond the speed of light. Relativity tells us this is impossible so what is the solution to this dilemma? Alternatively what is the source of energy driving the continued acceleration of Earth?

I'm a REer, but the FEers will bring up the Lorentz factor which basically says that an object with mass can never be accelerated to the speed of light. What I don't think I've seen an explanation for is the fact that their energy source would need to increase exponentially to keep a steady acceleration. The reason you can't get a massive object to the speed of light is because it would require an infinite amount of energy. Once again, just another flat Earth hack using only half of the facts.

[juner]

I'm a REer, but the FEers will bring up the Lorentz factor which basically says that an object with mass can never be accelerated to the speed of light. What I don't think I've seen an explanation for is the fact that their energy source would need to increase exponentially to keep a steady acceleration. The reason you can't get a massive object to the speed of light is because it would require an infinite amount of energy. Once again, just another flat Earth hack using only half of the facts.

It seems you are confusing proper acceleration with coordinate acceleration. UA may have flaws, but this isn't one of them.

[devils advocate]

It seems you are confusing proper acceleration with coordinate acceleration. UA may have flaws, but this isn't one of them.

Please then Junker can you shed some light on why the earth is accelerating at all? The start of this thread was asking for an explanation into the theory behind UA but so far there has been nothing offered as to what indicates that this is occurring, what the evidence is for it and what force started it. Also is everything in the universe moving in the same direction also.

[Curious Squirrel]

It seems you are confusing proper acceleration with coordinate acceleration. UA may have flaws, but this isn't one of them.

Please then Junker can you shed some light on why the earth is accelerating at all? The start of this thread was asking for an explanation into the theory behind UA but so far there has been nothing offered as to what indicates that this is occurring, what the evidence is for it and what force started it. Also is everything in the universe moving in the same direction also.

Basically, the UA exists because FE needs a way to explain RE's gravity. That's it. They have no experimental evidence for it, it's predicated on the idea that you need a way to have gravity. Thus, you get the UA (or the infinite plane Earth) to supply that to the flat Earth https://wiki.tfes.org/Universal_Acceleration Note they claim it's being done by Dark Energy, which just isn't well understood and mere conjecture on the part of all involved (with Dark Energy I mean, it's pretty specious even in the RE realm still as I recall, essentially an idea to explain observed oddities that is being worked on.)

[juner]

They have no experimental evidence for it, it's predicated on the idea that you need a way to have gravity.

I would suggest holding something (preferable not easily broken) in your hand a meter or more above the ground and letting it go. You can observe acceleration occur right before your eyes.

[Curious Squirrel]

They have no experimental evidence for it, it's predicated on the idea that you need a way to have gravity.

I would suggest holding something (preferable not easily broken) in your hand a meter or more above the ground and letting it go. You can observe acceleration occur right before your eyes.

Which is indistinguishable from gravity. So as not to upset Junker's sensitive little pedantic meter let me be clear. They have no direct evidence that shows something is accelerating the Earth, rather than an effect happening called gravity. The wiki page literally calls out that the two effects would be functionally the same via Relativity. But there's nothing (that I've ever seen shown) that would prove it's acceleration, and not gravity. As a reminder, the other hypothesis for FE asserts an infinite plane with normal gravity, as also listed on their wiki.

[juner]

Which is indistinguishable from gravity. So as not to upset Junker's sensitive little pedantic meter let me be clear. They have no direct evidence that shows something is accelerating the Earth, rather than an effect happening called gravity.

I think acceleration is much more easily-observed than gravity. Anyone can do it in a variety of ways. Observing gravity, though... That is another story.

[Ga_x2]

Which is indistinguishable from gravity. So as not to upset Junker's sensitive little pedantic meter let me be clear. They have no direct evidence that shows something is accelerating the Earth, rather than an effect happening called gravity.

I think acceleration is much more easily-observed than gravity. Anyone can do it in a variety of ways. Observing gravity, though... That is another story.

caaaaaveeeendiiiiish! 

[Curious Squirrel]

Which is indistinguishable from gravity. So as not to upset Junker's sensitive little pedantic meter let me be clear. They have no direct evidence that shows something is accelerating the Earth, rather than an effect happening called gravity.

I think acceleration is much more easily-observed than gravity. Anyone can do it in a variety of ways. Observing gravity, though... That is another story.

Yes, but saying "Watch this thing go from your hand to the ground. Acceleration!" is not one of them. Again, no evidence of an accelerating Earth as opposed to a globe Earth with gravity. UA seems designed with that literally in mind. It's not about observing acceleration vs observing gravity, it's about observing the Earth accelerating, vs seeing a round Earth that exhibits the effect we know as gravity. From a frame of reference upon the Earth, there is no difference. For being so pedantic you sure have a tough time grasping linguistic differences sometimes.

[juner]

caaaaaveeeendiiiiish! 

You think that is more easily observed than acceleration? I would suggest that you maybe do some research before posting. It will help to keep you from looking as ignorant as you do here.

Yes, but saying "Watch this thing go from your hand to the ground. Acceleration!" is not one of them.

Except it literally is an example of acceleration. Unless you are actually trying to argue that it isn't, which if you are then I suppose then isn't much left to discuss.

Again, no evidence of an accelerating Earth as opposed to a globe Earth with gravity.

Again, no evidence of a globe Earth with gravity as opposed to an accelerating Earth. See, I can do it too...

UA seems designed with that literally in mind. It's not about observing acceleration vs observing gravity, it's about observing the Earth accelerating, vs seeing a round Earth that exhibits the effect we know as gravity.

Cool, so how can we go about observing gravity? What is the mechanism that makes it function?

For being so pedantic you sure have a tough time grasping linguistic differences sometimes.

I am sorry if you are having trouble understanding simple concepts. I can try be even more simple with the explanations if you would prefer.

[Curious Squirrel]

Again, no evidence of an accelerating Earth as opposed to a globe Earth with gravity.

Again, no evidence of a globe Earth with gravity as opposed to an accelerating Earth. See, I can do it too...

UA seems designed with that literally in mind. It's not about observing acceleration vs observing gravity, it's about observing the Earth accelerating, vs seeing a round Earth that exhibits the effect we know as gravity.

Cool, so how can we go about observing gravity? What is the mechanism that makes it function?

The bolded is literally what I'm saying. The observation of a ball going from your hand to the ground isn't evidence either way based on how UA has been put forward. You presented it as though it was evidence of UA. It isn't a conclusive experiment in either direction.

The ease or not of replicating the Cavendish experiment has no bearing on UA not having any direct evidence for it. Can you show us the force that is making the Earth accelerate? Can you conclusively show us that it's the Earth accelerating towards the ball when we let got of it and not the ball accelerating towards the Earth? If you can I would love to see it.

[Ga_x2]

caaaaaveeeendiiiiish! 

You think that is more easily observed than acceleration? I would suggest that you maybe do some research before posting. It will help to keep you from looking as ignorant as you do here.

lol ok. Please explain the Cavendish experiment within the constraint of UA.

[juner]

Can you show us the force that is making the Earth accelerate? Can you conclusively show us that it's the Earth accelerating towards the ball when we let got of it and not the ball accelerating towards the Earth? If you can I would love to see it.

Not anymore than RE can show what makes gravity function, I suppose. But if you have some evidence to the contrary, I'd love to see it.

lol ok. Please explain the Cavendish experiment within the constraint of UA.

Nice deflection of the question. I would suggest you review the FAQ and the wiki.

[Curious Squirrel]

Can you show us the force that is making the Earth accelerate? Can you conclusively show us that it's the Earth accelerating towards the ball when we let got of it and not the ball accelerating towards the Earth? If you can I would love to see it.

Not anymore than RE can show what makes gravity function, I suppose. But if you have some evidence to the contrary, I'd love to see it.

Then stop claiming dropping a ball is evidence for UA. It's evidence for something bringing the ball from your hand to the ground.

[juner]

Can you show us the force that is making the Earth accelerate? Can you conclusively show us that it's the Earth accelerating towards the ball when we let got of it and not the ball accelerating towards the Earth? If you can I would love to see it.

Not anymore than RE can show what makes gravity function, I suppose. But if you have some evidence to the contrary, I'd love to see it.

Then stop claiming dropping a ball is evidence for UA. It's evidence for something bringing the ball from your hand to the ground.

Did I claim it was evidence for UA? I simply said it was evidence of acceleration.