# Fe gravity as it relates to the speed of light

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#### semperround

• 2903
##### Fe gravity as it relates to the speed of light
« on: July 05, 2006, 06:16:41 AM »
FE believers, correct me if i'm wrong, but the way I have seen how you describe gravity is that the earth is accelerating upward at a rate of 9.8m/sec^2. This, in theory, creates the gravity affect as it applies to us on the so called earth disc. If this is true, and the earth is constantly accelerating at the 9.8m/sec^2 rate, then by my calculations Earth would reach the speed of light at day 354 since it started falling and has been acclerating ever since. Was einstein wrong about the relativity thing? Please explain.
an vir

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#### Erasmus

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##### Fe gravity as it relates to the speed of light
« Reply #1 on: July 05, 2006, 01:09:40 PM »
Hi.  I'm going to sticky/lock this topic, because it's a pretty frequently-asked question that demands an explanation that is too long for the FAQ.

If you measure the speed of the Earth, you will notice it to be always zero.  That is, it's not getting any closer to you or farther from you, and it's not moving around in a circle.  If you're standing on the Earth, the Earth appears to be quite stationary.

Similarly, if you are in an automobile that is driving around a sharp turn, you will feel yourself pressed to one wall (the wall opposite the turn).  From your perspective, the automobile is stationary -- but, from your perspective, you can still tell that it is accelerating (or, equivalently, that it is generating a gravitational field).

On the other hand, as measured from somebody not in the car, the car is zipping around the turn -- i.e., moving and accelerating.  Similarly, the Flat Earth can be observed by others not on the Earth to be accelerating and moving upwards.  If you are worried that the Earth might eventually be going faster than the speed of light, you are only worried about it going faster than the speed of light as those observers measure it, not as we on the Earth measure it.

So, let's consider what happens from the perspective of one such observer -- call her Alice.  In particular, let's suppose Alice jumps over the ice wall into empty space (or whatever's there).  Since the Earth is no longer pushing her, she stops accelerating.  From her perspective, she is now at rest, and at the instant she jumps, the Earth is also at rest.  However, the Earth continues to accelerate upwards.

Let's say Bob stayed behind on Earth.  He measures the Earth's acceleration to be g = 9.8 m/s^2 -- the same way you might measure the accleration of the automobile going around the curve.  According to special relativity, Alice will measure a different acceleration -- in particular, she will measure it to be g/γ^3, where γ = 1/sqrt(1 - v^2/c^2).  In other words, we have the following differential equation for the velocity v of the Earth:  dv/dt = g/γ^3.

The solution to this equation is v = gt / sqrt( 1 + g^2t^2 / c^2 ), or v = g / sqrt(1/t^2 + g^2/c^2).  We are interested in the infinite time limit of v -- i.e. what happens to v as we wait an arbitrarily long time.  As t --> ∞, v --> g / sqrt(g^2/c^2) = c.

In other words, from Bob's perspective, the Earth is always stationary (we are Bob), but undergoing constant acceleration.  From Alice's perspective, the Earth moves at an ever increasing rate, but the acceleration is not constant -- it decreases over time in such a way that the Earth never surpasses the speed of light.

For more information, especially on the derivation and solution of the differential equation I presented, see p. 37 of "Introducing Einstein's Relativity" by Ray D'Inverno, in particular section 3.8.
Why did the chicken cross the Möbius strip?

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• 551
##### Fe gravity as it relates to the speed of light
« Reply #2 on: July 07, 2006, 03:49:55 AM »
Erasmus, you gave me the same explaination before for the time i asked the same question. And while you gave a wonderful explanation of the correctness of observers(they are all correct), I think you missed the point. Einstein also recognizes the existance of absolute spacetime. Meaning if the earth was constantly accellerating in a certain direction, it would come up against that nasty light-speed barrier through which matter cannot penetrate because it would be moving relative to SPACETIME. There are occurences of objects moving faster then the speed of light however. You are familar with the expanding universe and how the farther objects are, the faster they are moving away? It is possible for a galaxy to move away at faster then the speed of light. Picture the ballon analogy that I gave in another thread. Replace the dots, with pennies, it makes for a more accurate analogy as the forces inside the galaxies overcome the expansion of spacetime and stay together. As the ballon expands, the pennies get farther away from each other. blow it up to twice it's original size, and pennies that were 1cm apart are now 2cm apart. Pennies that were 10cm apart are now 20cm apart. The velocity at which the pennies move away from each other is proportional to their distance. Now apply to the actual universe. We see the same thing. Objects that are farther, are moving away faster. Doesn't this mean if an object is far enough, it CAN be moving away from us at FASTER then the speed of light. Yes it does.
The pennies aren't moving on the surface of the ballon, the ballon itself is expanding. We are only limited to less-then-light-speed travel as we move THROUGH space. This does not apply if space itself is expanding and causing the percieved velocity. Of course ontop of this space-time expansion our galaxy has excess velocity where it is actually moving through spacetime. And yes, there is a way to find exactly our excess velocity relative through spacetime.
The background radiation that permiates space from everywhere is incrediblly equal in all directions(meaning that we came from a very very low entropy big-bang). Much like how we can tell how fast distant galaxies are moving from us via analyzing the light of their emitted stars and factoring in the doppler effect, we can do the same for us and the background radiation. We actually DO receive higher frequency background radiation on one side of the earth while getting lower frequency radiation on the other. All scientists do is factor in the doppler effect and figure out what direction and velocity we would have to move in for it to be equal from all sides. From this we can figure out our excess velocity. Also from this, and more importantly the point of this post, we can figure out a theoretical absolute state of rest in relation to spacetime in the universe.

The point is that there is infact an absolute to be moving in reference too when talking about motion. And there is a way to determine it. If the earth was accellerating "upwards" at 9.8m/s/s then at some point it would come up against the barrier of lightspeed and it's mass would get larger and larger and it would enter into a period of ever-increasing decellerating-accelleration as it cannot cross that barrier. Meaning after a year of accellerating at 9.8m/s/s the preceived gravity would become less and less. And no, since you must be accellerating through spacetime to experience gravity, one cannot somehow hijack the expanding spacetime model and change it into the reasoning behind why the earth can travel at a constant 9.8m/s/s.

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#### Erasmus

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##### Fe gravity as it relates to the speed of light
« Reply #3 on: July 07, 2006, 10:50:00 AM »
I'm so fervently opposed to this notion of "relative to spacetime" that I absolutely insist on references.  Your claims of "absolute rest" seem to violate the very foundational postulates of relativity theory.

That said, I never claimed that the Earth would go faster than the speed of light relative to anything.  The entire gist of my post was to reproduce a proof that a constant acceleration (and linearly increasing velocity) in one frame of reference translates to asympotitic acceleration (and asymptotic velocity with asymptote at v = c) in any inertial frame of reference.  Which part of that do you disagree with?
Why did the chicken cross the Möbius strip?

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• 551
##### Fe gravity as it relates to the speed of light
« Reply #4 on: July 07, 2006, 07:38:42 PM »
Quote from: "Erasmus"
I'm so fervently opposed to this notion of "relative to spacetime" that I absolutely insist on references.  Your claims of "absolute rest" seem to violate the very foundational postulates of relativity theory.

That said, I never claimed that the Earth would go faster than the speed of light relative to anything.  The entire gist of my post was to reproduce a proof that a constant acceleration (and linearly increasing velocity) in one frame of reference translates to asympotitic acceleration (and asymptotic velocity with asymptote at v = c) in any inertial frame of reference.  Which part of that do you disagree with?

I disagree with your notion that the earth could travel at 9.8m/s/s forever through spacetime. It would eventually hit the light-speed barrier. Unless the earth has no mass, it cannot cross into this velocity.

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#### 6strings

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##### Fe gravity as it relates to the speed of light
« Reply #5 on: July 07, 2006, 08:02:16 PM »
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I disagree with your notion that the earth could travel at 9.8m/s/s forever through spacetime. It would eventually hit the light-speed barrier. Unless the earth has no mass, it cannot cross into this velocity.

...There is no light-speed barrier...

From reading your posts on the speed of light in the thread "faster than light", your notion of "absolute spacetime" seems to be rooted in the fact tht something always has a velocity of 300,000 m/s in space and time, and thus, logically, can not surpass said velocity.

This seems to be a simple misunderstanding, though.  You see, in reality, people will always measure their velocity through spacetime to be the speed of light.  An object, that, in its own frame of reference, is at rest, will meaure it's velocity through space to be 0 m/s and through time, be 300,000 m/s, whereas an observer from an outside frame of reference will measure it differently, in the manner described by Erasmus, in the case of an accelerating object.

Of course, I'm merely basing this off your posts in another thread, and what I believe to be your position, feel free to tell my if I've constructed a strawman.

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• 551
##### Fe gravity as it relates to the speed of light
« Reply #6 on: July 08, 2006, 07:06:31 AM »
Quote from: "6strings"
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I disagree with your notion that the earth could travel at 9.8m/s/s forever through spacetime. It would eventually hit the light-speed barrier. Unless the earth has no mass, it cannot cross into this velocity.

...There is no light-speed barrier...

From reading your posts on the speed of light in the thread "faster than light", your notion of "absolute spacetime" seems to be rooted in the fact tht something always has a velocity of 300,000 m/s in space and time, and thus, logically, can not surpass said velocity.

This seems to be a simple misunderstanding, though.  You see, in reality, people will always measure their velocity through spacetime to be the speed of light.  An object, that, in its own frame of reference, is at rest, will meaure it's velocity through space to be 0 m/s and through time, be 300,000 m/s, whereas an observer from an outside frame of reference will measure it differently, in the manner described by Erasmus, in the case of an accelerating object.

Of course, I'm merely basing this off your posts in another thread, and what I believe to be your position, feel free to tell my if I've constructed a strawman.

Yes but for the sake for this arguement I am ignoring the effects of time when travelling through spacetime. They aren't important to the issue at hand. It just seems that Erasmus has overlooked Einstein's notion of absolute spacetime. Yes it may be dynamic and changing to objects within it, but it still is an absolute. And e=mc2 also. meaning if you accellerate in a direction, you will feel the effects of it at some point(you could of been moving or accellerating in the other direction to start) And you are also completely leaving out Higgs fields. The electroweak higgs field(sometimes referred to as the Higgs Ocean) is the theoretical field that gives objects their mass. They have been predicted mathmatically and it is just a matter for the next generation of atom smashers to find them in the real world (2007). If they do exist, then we would know that there would be a field (much like the old notion of the aether) that objects do infact travel through. Making the idea that the earth travels through it an accellerating 9.8m/s/s impossible according to physics.

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#### Erasmus

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##### Fe gravity as it relates to the speed of light
« Reply #7 on: July 08, 2006, 08:45:18 AM »
Troubadour: you seem to be jumping all over the place.  You also have not given references to this absolute spacetime / light-barrier notion.

I have provided an explanation as to how an object can in one reference frame undergo a constant acceleration, and in another reference frame undergo an ever-decreasing acceleration.  In both frames, the object in question is shown never to travel past the speed of light.

As far as "speed relative to spacetime" is concerned, there is no such thing as linear acceleration.  When you consider spacetime as a unified geometric space, "speed" has no meaning, but any massive object has a four-velocity which is a vector tangent to its world-line.  This vector always has magnitude 1 (or c, depending on your units), and so in that sense velocity in spacetime is constant.

When we talk about "velocity" we are referring only to rate of travel through space, or, the projection of an object's four-velocity onto the spacelike coordinates.

I disagree with your notion that the earth could travel at 9.8m/s/s forever through spacetime. It would eventually hit the light-speed barrier. Unless the earth has no mass, it cannot cross into this velocity.
is totally without meaning.  "9.8 m/s/s" is not a rate at which one can travel through spacetime.  I also never claimed that the Earth would, in any reference frame, ever be travelling at the speed of light; I spoke only in terms of limits.  Lastly, I don't at all understand
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I am ignoring the effects of time when travelling through spacetime
, nor do I understand how "E = mc^2" is relevant, nor do I see how the hypothetical Higgs field is relevant, nor do I know what you mean by Einstein's notion of absolute spacetime (I thought I did, but I feel like we don't agree on what that means).

In any case, I don't feel you have addressed the argument I've made -- finding the Lorentz transformation of a constantly accelerating object -- which came straight out of a rather rigorous text on relativity.  I am fairly convinced that this view of relativity theory is correct and that yours is flawed; please either read the reference I have provided, or provide references supporting your own position.
Why did the chicken cross the Möbius strip?

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• 551
##### Fe gravity as it relates to the speed of light
« Reply #8 on: July 08, 2006, 08:03:44 PM »
So you are saying that the Flat Earth theory of earth's simulated gravity picks and chooses what it wants from relativity. Let me jump to a better defense of my position then the relativity one. I will come back to that later. Right now I will defend my absolute  spacetime notion.
2 spaceships start right next to each other. They are sufficently away from any large bodies gravity so it is just the 2 spaceships alone in empty(empty is accually misleading) space. They both star accellerating away from each other at the rate of 9.8 Meters Per second, every second. Meaning at 1 second, they have moved 9.8 meters from their original position. at 2 seconds they will be 29.4 Meters from their original position as they will of accellerated an additional 9.8 meters from the first second, putting their velocity from the starting point at 19.6m/s. Of course from spaceship 1, spaceship 2 is getting farther and farther, but a rate that is equal to it's own distance from the starting point x 2, as it's accellerating at the same rate spaceship 1 is in the opposite direction. got all this so far?
Let's say these spaceships were shaped like towers and they had both started with their bottoms to each other, one mirroring the other. They all have floors and such like a building also. The people in spaceship 1 will be experiencing a pull down to the "floor" equal to earth's as they are accellerating at 9.8m/s/s. The people in spaceship 2 will also be experiencing earthlike pull to the floor as they will be accellerating at 9.8m/s/s. But, to spaceship 1, spaceship 2 is accellerating away at 19.6m/s/s. So if we were on spaceship 1, we could say that the people on spaceship 2 should be experiencing 2 Gs, but they aren't. They are experiencing 1G. This shows the universe obviously isn't derived from the observations of spaceship 1. We can figure this out because spaceship 1 is experiencing a G itself from accelleration. So we can figure out that ship 2 is getting 1 G. But here is the bigger question. What is causing the people in the ship to be drawn to the floor? What causes the resistance to accelleration? Doesn't the very fact that there is a resistance to accelleration prove that there is some kind of medium that matter is moving through? Meaning that even with no other objects to be in reference too, you WILL feel forces from accelleration and be subject to the same laws of the universe, and there are situation where one observer can be incorrect of it's observations of another.

to be continued.

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#### Erasmus

• The Elder Ones
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##### Fe gravity as it relates to the speed of light
« Reply #9 on: July 08, 2006, 11:21:35 PM »
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The people in spaceship 2 will also be experiencing earthlike pull to the floor as they will be accellerating at 9.8m/s/s. But, to spaceship 1, spaceship 2 is accellerating away at 19.6m/s/s.

No it isn't.  You're begging the question here: accelerations don't add the way they do in Galilean relativity.

Imagine the buildings aren't accelerating.  Instead, suppose you and I are floating (inertially) out in space and the two buildings pass by us in opposite directions, each with speed 0.75 c.  You're not going to suggest that, as measured by the people in one building, the people in the other building are going at velocity 1.5 c, are you?

Of course not, because you can't just add velocities in special relativity.  Similarly, you cannot just add accelerations.  Just because (back in the accelerating-building scenario) to an inertial observer, the two buildings are each accelerating at 1g, it doesn't imply that to an observer in one building, the people in the other building are accelerating away at 2g.

If anybody's picking and choosing which bits of relativity they want to use, it's you, who believes that you can add velocities willy-nilly without taking into account the Lorentz transformations between observers.
Why did the chicken cross the Möbius strip?

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• 551
##### Fe gravity as it relates to the speed of light
« Reply #10 on: July 09, 2006, 07:56:38 AM »
For the speeds and velocities I am talking about, there is no need to bother with the Lorentz transformations. Much like how as long as I'm not talking about very fast speeds or very large gravitational fields, newtonian physics works just fine for predictions. And here, from the GSU physics site on lorentz transformations:

c as Speed Limit

The speed of light c is said to be the speed limit of the universe because nothing can be accelerated to the speed of light with respect to you. A common way of describing this situation is to say that as an object approaches the speed of light, its mass increases and more force must be exerted to produce a given acceleration. There are difficulties with the "changing mass" perspective, and it is generally preferrable to say that the relativistic momentum and relativistic energy approach infinity at the speed of light. Since the net applied force is equal to the rate of change of momentum and the work done is equal to the change in energy, it would take an infinite time and an infinite amount of work to accelerate an object to the speed of light. (Sorry, Captain Kirk. We can't give you warp speed!)

A common resistance to the speed limit is to suggest that you just accelerate two different objects to more than half of the speed of light and point them toward each other, giving a relative speed greater than c. But that doesn't work! Time and space are interwoven in such a way that no one observer ever sees another object moving toward them at greater than c. The Einstein velocity addition deals with the transformation of velocities, always yielding a relative velocity less than c. It doesn't agree with your common sense, but it appears to be the way the universe works.

Matter cannot move faster then the speed of light through spacetime. The point at which I've been trying to get at this entire time. I say through spacetime because there exist in theory distant galaxies which could be moving away from us faster then the speed of light due to the expansion of spacetime(ballon analogy). The light from these galaxies will never be able to reach us however, so we cannot observe them. It would only take a year before the Earth's velocity in said FE theory would be nearing the speed of light, meaning it would not be able to maintain a 9.8m/s/s accelleration as it got closer and closer to the speed of like. It would start slowing it's decelleration. It could keep doing this for infinity if you like, getting closer and closer to the speed of light, but never quite reaching it. But it would not be able to travel as fast as light itself(or faster). This means it could not maintain a 9.8m/s/s accelleration needed to simulate gravity for very long.

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#### Erasmus

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##### Fe gravity as it relates to the speed of light
« Reply #11 on: July 09, 2006, 10:11:09 AM »
For the speeds and velocities I am talking about, there is no need to bother with the Lorentz transformations.

Obviously not, since we both agree that eventually the Earth/buildings/whatever will be going at least near the speed of light.

The speed of light c is said to be the speed limit of the universe because nothing can be accelerated to the speed of light with respect to you.

Emphasis added by me.  Note that it says "with respect to you", not "with respect to spacetime".

Furthermore,

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it would take an infinite time and an infinite amount of work to accelerate an object to the speed of light.

Which is exactly what I describe in my original post -- the behavior of the Earth in the limit of infinite time.

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A common resistance to the speed limit is to suggest that you just accelerate two different objects to more than half of the speed of light and point them toward each other, giving a relative speed greater than c. But that doesn't work!

Again, exactly what I stated above.  If you tried this two-buildings-accelerating thing, neither of them would observe the other to be moving faster than light, ever.

Matter cannot move faster then the speed of light through spacetime. The point at which I've been trying to get at this entire time.

And which, I'm telling you, reflects a misunderstanding of the word "relative".  All objects have the same speed in spacetime (a statement I've made repeatedly) and this this speed never ever changes for any object under any circumstances.

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... meaning it would not be able to maintain a 9.8m/s/s accelleration as it got closer and closer to the speed of like. It would start slowing it's decelleration.

That's true, from the perspective of an inertial observer.

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It could keep doing this for infinity if you like, getting closer and closer to the speed of light, but never quite reaching it. But it would not be able to travel as fast as light itself(or faster). This means it could not maintain a 9.8m/s/s accelleration needed to simulate gravity for very long.

Only from the viewpoint of somebody not on the Earth.  From the viewpoint of somebody on the Earth, this acceleration can continue indefinitely.  The Lorentz transformation nicely converts constant acceleration in one frame to asymptotically decreasing acceleration in another.  Did you read anything I posted?

Look, if you're confident in your interpretation of SR, why don't you give a quantitative description of exactly what will happen in the accelerating-Earth model, both in the reference frame of an inertial observer A and in the reference frame of some accelerating observer B on the Earth?  These little discussions are great but it would be interesting to see if you could take the theorems of relativity and use them to rigorously demonstrate what you're claiming would happen.
Why did the chicken cross the Möbius strip?

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• 551
##### Fe gravity as it relates to the speed of light
« Reply #12 on: July 09, 2006, 09:00:44 PM »
Quote from: "Erasmus"

Again, exactly what I stated above. If you tried this two-buildings-accelerating thing, neither of them would observe the other to be moving faster than light, ever.

I never claimed that the buildings could view each other as moving at the speed of light, ever. I did mention previously that via the expansion of the universe, it is possible for objects to move away from each other (or toward each other) at or greater then the speed of light. think ballon analogy. if the pennies are sufficiently far away from each other, they CAN move away from each other at the speed of light because the farther they are, the faster they are moving apart. The pennies however are not moving, the space is just expanding around them, so there is no interference with relativity.

I'm working on the large and more well defined idea of what i'm proposing. But I work for a living, and you want me to start using equations, so it will take me some time.

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• 551
##### Fe gravity as it relates to the speed of light
« Reply #13 on: July 10, 2006, 10:27:35 PM »
I sent an e-mail last night to a distinguished professor(Robert B. Hallock, graduate of UMASS, masters and Ph.D at Stanford) that I spoke with on campus a few months ago describing my view of what would happen to an object with a constant accelleration.

I simply said I was having a debate with someone about an object that is accellerating at a constant rate of 9.8m/s/s through a vacuum. I said that they claimed it could accellerate forever and simulate the earth's gravity, and that I said that it would eventually enter into a period of ever-decellerating accelleration as it neared the speed of light and the effects of the percieved gravity would diminish. Here is what he said.

Quote from: "Prof. Hallock"

According to the classical newton universe, the object will accellerate forever as long as no other forces act upon it. So your friend would be correct if this was the way the universe worked. But lucky for you it is not.
Taking General Relativity into account, nothing can travel faster then c, or the speed of light in a vacuum. We have to ignore the source of the accelleration for the object because to propel even single particles to near the speed of light requires an incredible amount of energy. But ignoring that no, in General Relativity you could not exceed c, nor could you maintain a 9.8m/s accelleration forever.  As the object approaches c, the accelleration would decrease exponentially. The object will never reach c, but it will get closer and closer to it. As the accelleration decreased, so would the effects of the push to anything on the surface of the object. You can tell your friend that he is incorrect.

There is no need for me to talk any further about this as I have been confirmed by an actual physicist. Sorry FE theory. You'll have to come up with another reason for earth's gravity.

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#### Erasmus

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##### Fe gravity as it relates to the speed of light
« Reply #14 on: July 11, 2006, 12:05:05 AM »
Thanks for the reference.  I'm a little worried that you may have misrepesented the hypothesis, but I'll just assume you did not.  In any case, Dr. Hallock and I agree that as measured from an inertial frame, the Earth's velocity would only asymptotically approach c.  We only disagree on what would happen in the frame of reference of the ship.

As a thought experiment, consider what would happen if the Earth (spaceship, whatever) suddenly stopped accelerating.  Now it's inertial again, meaning it's at rest again, meaning it should be able to accelerate from 0 all over again, because all inertial reference frames are equivalent.  If you are right, then upon starting to accelerate again, the passengers on the ship would not feel the same artificial gravity that they felt the first time the ship starts accelerating, which would give them an experiment to test for "absolute rest", which is a glaring contradiction to the principle of relativity.
Why did the chicken cross the Möbius strip?

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• 551
##### Fe gravity as it relates to the speed of light
« Reply #15 on: July 11, 2006, 12:28:05 AM »
Quote from: "Erasmus"
Thanks for the reference.  I'm a little worried that you may have misrepesented the hypothesis, but I'll just assume you did not.  In any case, Dr. Hallock and I agree that as measured from an inertial frame, the Earth's velocity would only asymptotically approach c.  We only disagree on what would happen in the frame of reference of the ship.

As a thought experiment, consider what would happen if the Earth (spaceship, whatever) suddenly stopped accelerating.  Now it's inertial again, meaning it's at rest again, meaning it should be able to accelerate from 0 all over again, because all inertial reference frames are equivalent.  If you are right, then upon starting to accelerate again, the passengers on the ship would not feel the same artificial gravity that they felt the first time the ship starts accelerating, which would give them an experiment to test for "absolute rest", which is a glaring contradiction to the principle of relativity.

If it stopped accellerating, it would still have it's remaining velocity.

Also, there is a state of absolute rest in any frame and can be determined. I mentioned using the background radiation as a way to find a state of rest before. Here is a better explanation I found from Edward J. Barlow's (recipient of NASA public service award) General Relativity section in his introduction into cosmology (http://www.cosmologymodels.com/index2.html).

Quote from: "Barlow"

While in special relativity there is no standard of rest and no preferred reference frame, in general relativity the situation is somewhat different. A rest frame for any particular region of space can be defined as the frame which is not rotating compared to the background of distant stars and for which the cosmic microwave background radiation, CMBR, has the same spectrum in all directions and so the concept of local motion in that frame is meaningful. In another region of space, there would also be a rest frame for which the CMBR is the same in all directions, but the two rest frames are moving with respect to each other so there is no preferred frame of that type for the universe as a whole and no center of the universe. We can however, define a comoving rest frame for the universe as a whole for which the requirement of the CMBR being the same in all directions and there being a standard of rotation based on the distant stars is met at all locations.

Also, you threw me way off with the lorentz transformations. I didn't see how they applied to what I was proposing and thought you figured out something I didn't. Turns out I think you just misunderstood me the entire time.

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#### Erasmus

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##### Fe gravity as it relates to the speed of light
« Reply #16 on: July 11, 2006, 12:17:51 PM »
So your conclusion then is that the Principle of Relativity -- that all inertial observers are equivalent -- is wrong?

The primary statement of yours that supports this conclusion is

If it stopped accellerating, it would still have it's remaining velocity.

Remember that there are two inertial reference frames.  The ship started off at rest in S, then accelerated for a while, then stopped accelerating, so that it is now at rest in inertial frame S'.  According to SR, S and S' ought to be equivalent.  Do you disagree with this?

As for the CMBR -- the exact way in which this information affects the notion of absolute reference frame is not clear to me.  For example, what happens if I enclose my ship in a sphere that blocks this radiation?  Then, whenever I measure this radiation, I find the spectrum to be the same in all directions.
Why did the chicken cross the Möbius strip?

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#### Erasmus

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##### Fe gravity as it relates to the speed of light
« Reply #17 on: July 14, 2006, 04:34:47 PM »
Also, there is a state of absolute rest in any frame and can be determined. I mentioned using the background radiation as a way to find a state of rest before.

Just out of curiosity, what's the Earth's velocity with respect to the CMBR?  Also, what makes the CMBR a preferred reference frame?
Why did the chicken cross the Möbius strip?

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#### Aralith

• 322
##### Fe gravity as it relates to the speed of light
« Reply #18 on: July 14, 2006, 05:28:14 PM »
Well, did any of you know that science has now proven two things: 1. That a light pulse can travel faster than light (since light is both a particle, and a wave, this might suggest that objects can too) and 2. that said light pulse actually arrived before it left when it traveled faster than light. This means, that it essentially travelled back in time. This notion may seem ridiculous, but I have provided a link to the article. This suggests that it might be possible for matter to break the light speed barrier under very specific conditions. So, let's say the earth is flat (but it's not). And then let's say that these specific conditions are met somehow, and the earth starts travelling upwards at a speed faster than the speed of light. Well, then we would all be travelling backwards in time, which we know is not true. Therefore, the earth cannot be constantly gaining speed (not only because it can't travel faster than light without travelling back in time, but also because of the obvious reason that there is nothing propelling it upwards) because, as was stated in the beginning of this thread, the earth would have broken the light speed barrier by day 354. Well, the earth has obviously been around much longer than that, so it would already be travelling faster than light, which can't be possible, or we would be moving backwards in time. Hope this settles the gravity factor once and for all, but I'm expecting a bunch of conspiracy claims, so it probably won't.
am a round-earther traversing this site to disprove false claims and bring the light of science to those who remain in the dark without it. Thank you for your time.

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#### 6strings

• The Elder Ones
• 689
##### Fe gravity as it relates to the speed of light
« Reply #19 on: July 14, 2006, 05:35:20 PM »
That is only because the object in question has been accelerated to a velocity exceding c with respect to us.

Do you think that we're at complete rest on our planet, regardless of whether you believe in RE or FE?  Because your argument would only hold any amount of water if that were the case, but it isn't.  We are hurtling through space at enormous velocities, so according to your own logic, we should not be able to accelerate things past (the speed of light-our own velocity through space) before they go back in time...

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#### Aralith

• 322
##### Fe gravity as it relates to the speed of light
« Reply #20 on: July 14, 2006, 05:37:53 PM »
What? I don't understand your post at all 6strings. Please elaborate. Also, I agree that we're moving through space, but we're not accelerating. The earth rotates on its axis at a constant speed. The earth moves around the sun at a constant speed. What acceleration are you talking about? According to RE theory, we're not accelerating, but staying at a constant speed.
am a round-earther traversing this site to disprove false claims and bring the light of science to those who remain in the dark without it. Thank you for your time.

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#### 6strings

• The Elder Ones
• 689
##### Fe gravity as it relates to the speed of light
« Reply #21 on: July 14, 2006, 05:59:27 PM »
Alright, you are taking the speed of light, c, as an absolute value, and if an object is accelerated to a velocity exceeding c, it goes back in time.  The reality of the matter is that c is defined in relation to you, that is to say, the effects of greater-than-light-speed travel only come into effect if an object exceeds c in relation to you.

Such is demonstrated by the fact that we still needed to accelerate the particles to 3.0*10^8 m/s (approximating c to 3.0*10^8 m/s), even though, according to RE, we are hurtling through space at high velocities.  Hypothetically, if nothing could go faster than c anywhere, we would only have to accelerate the paraticles to the velocity expressed by:
c-(whatever the speed we are moving at, of which I am woefully ignorant).

In any case, the point remains that it is merely movements at speeds approaching c, in relation to us, that we must concern ourselves with.

Furthermore, if you have any more issues with this, feel free to use the search function to find more threads that have adressed this issue, or PM me (don't start a speed of light thread, because we've had to many already).  I feel bad about highjacking this thread, as it was supposed to be a definitive resolution to the issue.  Erasmus, or any other mod, feel free to delete these posts from the thread if you feel they're cluttering up space.

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#### Ubuntu

• 2392
##### --
« Reply #22 on: July 14, 2006, 06:08:34 PM »
Erasmus, what place do you have debating science when it's all a government conspiracy anyways? Einstein must have been part of the conspiracy too, so how can you trust him?

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• 551
##### Fe gravity as it relates to the speed of light
« Reply #23 on: July 14, 2006, 11:55:22 PM »
Quote from: "Erasmus"
Also, there is a state of absolute rest in any frame and can be determined. I mentioned using the background radiation as a way to find a state of rest before.

Just out of curiosity, what's the Earth's velocity with respect to the CMBR?  Also, what makes the CMBR a preferred reference frame?

The CMBR's source is the big bang, the beginning of space and time. If you get to the point where it is even in all directions (no red or blue shift), then you are at rest in relation to spacetime.

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• 551
##### Fe gravity as it relates to the speed of light
« Reply #24 on: July 15, 2006, 12:12:10 AM »
Quote from: "Aralith"
Well, did any of you know that science has now proven two things: 1. That a light pulse can travel faster than light (since light is both a particle, and a wave, this might suggest that objects can too) and 2. that said light pulse actually arrived before it left when it traveled faster than light. This means, that it essentially travelled back in time. This notion may seem ridiculous, but I have provided a link to the article. This suggests that it might be possible for matter to break the light speed barrier under very specific conditions. So, let's say the earth is flat (but it's not). And then let's say that these specific conditions are met somehow, and the earth starts travelling upwards at a speed faster than the speed of light. Well, then we would all be travelling backwards in time, which we know is not true. Therefore, the earth cannot be constantly gaining speed (not only because it can't travel faster than light without travelling back in time, but also because of the obvious reason that there is nothing propelling it upwards) because, as was stated in the beginning of this thread, the earth would have broken the light speed barrier by day 354. Well, the earth has obviously been around much longer than that, so it would already be travelling faster than light, which can't be possible, or we would be moving backwards in time. Hope this settles the gravity factor once and for all, but I'm expecting a bunch of conspiracy claims, so it probably won't.

Black Holes emit raditation, which is against classical physics as nothing should be able to escape. But since in quantum mechanics, there are no 0 probabilites for particles in a quantum state (IE before the collaspe of the wave function), there are potentials for particles to travel faster then the speed of light just long enough to travel out of the black hole. Thereby causeing radiation. Of course this has been explained another way.

Imagine in space 2 photons collide with enough force to produce an electron and it's anti-matter twin, a positron(they are always created in pairs like this). Imagine the electron as a particle travelling forward through time, and the positron as the same electron, but travelling backwards in time. So when the electron travels forward through time, it appears as an electron. When it travels backwards through time, it is a positron. It the electron get's trapped inside of a black hole, then it would be possible for the positron to travel backwards through time out of the black hole. This also works in the reverse. The positron could fall into the black hole. So then at some point, that electron that was previously travelling back through time as a positron into the black hole, can travel forward through time out of the black hole.

And there is yet another theory involving the theoretical electroweak higgs field, the field that gives all particles their mass. This field becomes so disrupted inside the black hole, that it allows particles to become massless and be able to travel faster then light out of the black hole.

Hawking has a theory that as black holes radiate away energy, they loose their mass and slowly dissolve away until they loose the critical mass size to stay black holes. All he needs to prove this theory is to find an aging black hole. But it is thought that it might take billions and billions of years for this to happen to even smaller black holes. And since the universe has only been around for about 15 billion years, it's unlikely he will find a black hole of the appropriate age.

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#### Erasmus

• The Elder Ones
• 4242
##### Fe gravity as it relates to the speed of light
« Reply #25 on: July 15, 2006, 11:27:14 PM »
Quote from: "Erasmus"
Just out of curiosity, what's the Earth's velocity with respect to the CMBR?  Also, what makes the CMBR a preferred reference frame?

The CMBR's source is the big bang, the beginning of space and time. If you get to the point where it is even in all directions (no red or blue shift), then you are at rest in relation to spacetime.

Um, obviously all that means is that you're at rest relative to the CMBR.

So what about the Earth's velocity w.r.t. the CMBR?
Why did the chicken cross the Möbius strip?

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#### Jenks

##### Fe gravity as it relates to the speed of light
« Reply #26 on: July 17, 2006, 08:33:18 AM »
If gravity is the earth accelerating upwards, then does that mean FEers don't believe gravity has a relation to mass? And if so this would mean the moon doesn't have 'gravity' as we know it, so what creates the tides on our seas?

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#### Erasmus

• The Elder Ones
• 4242
##### Fe gravity as it relates to the speed of light
« Reply #27 on: July 17, 2006, 09:25:35 AM »
Quote from: "Jenks"
If gravity is the earth accelerating upwards, then does that mean FEers don't believe gravity has a relation to mass?

There are several kinds of mass: inertial, passive gravitational (for reacting to gravitational fields), and active gravitational (for generating gravitational fields).  In Newtonian theory, it is purely coincidental that these are equal.  In FE, it is not assumed that they are universally equal for all materials.
Why did the chicken cross the Möbius strip?

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#### CrimsonKing

• 1621
##### Fe gravity as it relates to the speed of light
« Reply #28 on: July 17, 2006, 09:39:40 AM »
As for the tides, one of the major ideas is that the earth has a slight seesaw effect.
he man in black fled across the desert, and the gunslinger followed.

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• 551
##### Fe gravity as it relates to the speed of light
« Reply #29 on: July 17, 2006, 10:16:39 PM »
Quote from: "Erasmus"
Quote from: "Erasmus"
Just out of curiosity, what's the Earth's velocity with respect to the CMBR?  Also, what makes the CMBR a preferred reference frame?

The CMBR's source is the big bang, the beginning of space and time. If you get to the point where it is even in all directions (no red or blue shift), then you are at rest in relation to spacetime.

Um, obviously all that means is that you're at rest relative to the CMBR.

So what about the Earth's velocity w.r.t. the CMBR?

WTR?