What is EU argument/evidence for gravity faster than light?

[Muskie]

I recently watched youtube https://www.youtube.com/watch?v=ZEYdsZFNOrE where Bishop Nicholas Sykes reasoned that if the Sun disappeared we wouldn't see this for 8 minutes, i.e., speed of light, but that the Earth's orbit actually depends on where it is now - not 8 minutes ago. That if it depended upon where it was 8 minutes ago "it would be slung out of orbit in short order." Can someone explain how the Earth would be "slung out of orbit in short order?" I don't understand the reasoning or mechanics of why this would happen.

If there are other arguments and evidences of gravity being (much) faster than light, I'd definitely appreciate hearing about it or being pointed to a link. (I realize this subject has been covered here, but I seem to be just finding pieces in other threads. Could be too I am lazy. I call it efficient!)

Thanks.

[upriver]

I like to refer to Tom Van Flanderns page to start with.

https://web.archive.org/web/20120428223 ... ravity.asp

[Muskie]

Whoa! Thank you!

[D_Archer]

Basically EU says that there is 'longitudinal force', whatever the medium this force is transmitted in (ether, or photons) it is faster than a transverse wave.

Regards,
Daniel

[jacmac]

The explanations and discussions about the "SPEED OF GRAVITY" all seem to have the basic notion that gravity is pulsed. The pulse is a quickly repeating question of "where are you now?" It is Like those old cell phone commercials where the man takes a few steps and says again "can you hear me now ?" And because of the needs of the physics, the eight minute delay from sun to earth notwithstanding, the gravity pulse is said to be instantaneous.

I think there is something else going on. With a body in orbit about another, there is an ongoing relationship, almost as if each KNOWS where the other is in an ongoing manner. How to describe this in physics terms is instant action at a distance no doubt, but leave me wondering...

The instant action at a distance, bending of space time, longitude waves etc. all seem to be a scientific way of saying, WE DON'T KNOW.

Jack

[upriver]

There are longitudinal forces in water, pressure waves. They dont go FTL.

"Emanuele Fiandrini · INFN - Istituto Nazionale di Fisica Nucleare
The correct answer to ask is: which are the medium properties that allow for a transverse and longitudinal wave propagation?
The answer is that when a perturbation displaces a medium element from its equilibrium position, there must be a force in the medium that brings back the element to the original equilibrium position.
Now, for the longitudinal waves the force is the pressure force: when you try to compress a body, pressure opposes to compression and tends to bring back the body at its original; for tranverse waves, you need to have a shear force that restores the original position.
By definition, a fluid is a medium that does not oppose resistance to shear forces, but only to rate of shear deformation, that is if you try to deform a fluid element you dont get any elastic restoring shear force, that is proportional to the deformation, but only a resistance to how much rapidly the element is deformed, that is a force proportional to the speed gradient, the proportionality coeff is the viscosity. In solids, instead, if you try to deform an element of the body, shear forces will tend to restore its original form, that is there is an elastic (in the limit of small deformations) shear stress opposes to deformations (it's the generalization of hooke's law). That's why you may have transverse waves in solids but not in fluids.
A different case are the surface waves, like sea waves."

So it would be my guess that to have an electrical force that was FTL you need to have a medium that can transmit FTL.
So now we are talking about what is an electrical field.
And what might be the properties that it will allow FTL energy transfer...

[lamare]

There are longitudinal forces in water, pressure waves. They dont go FTL.

"Emanuele Fiandrini · INFN - Istituto Nazionale di Fisica Nucleare
The correct answer to ask is: which are the medium properties that allow for a transverse and longitudinal wave propagation?
The answer is that when a perturbation displaces a medium element from its equilibrium position, there must be a force in the medium that brings back the element to the original equilibrium position.
Now, for the longitudinal waves the force is the pressure force: when you try to compress a body, pressure opposes to compression and tends to bring back the body at its original; for tranverse waves, you need to have a shear force that restores the original position.
By definition, a fluid is a medium that does not oppose resistance to shear forces, but only to rate of shear deformation, that is if you try to deform a fluid element you dont get any elastic restoring shear force, that is proportional to the deformation, but only a resistance to how much rapidly the element is deformed, that is a force proportional to the speed gradient, the proportionality coeff is the viscosity. In solids, instead, if you try to deform an element of the body, shear forces will tend to restore its original form, that is there is an elastic (in the limit of small deformations) shear stress opposes to deformations (it's the generalization of hooke's law). That's why you may have transverse waves in solids but not in fluids.
A different case are the surface waves, like sea waves."

So it would be my guess that to have an electrical force that was FTL you need to have a medium that can transmit FTL.
So now we are talking about what is an electrical field.
And what might be the properties that it will allow FTL energy transfer...

There is another type of "wave" which is neither transverse nor longitudinal and which does propagate trough a fluid;

an (expanding) vortex ring.

This not only resolves the problem of how "transverse waves" could propagate trough a fluid medium (they are actually expanding vortex rings misinterpreted as being transverse waves), but also resolves the difference between the "near" and "far fields" very nicely.

It appears that both a transverse wave and an expanding vortex ring propagate at c, while a longitudinal wave propagates at sqrt(3) times c.

I have recently re-derived Maxwell's equations from a basic aether model, in which gravity is also incorporated as the Laplacian (2nd order derivative) of the Electric field, which would lead to the conclusion that gravity waves are standing longitudinal waves:

http://www.tuks.nl/wiki/index.php/Main/ ... Everything

[Michael Mozina]

I recently watched youtube https://www.youtube.com/watch?v=ZEYdsZFNOrE where Bishop Nicholas Sykes reasoned that if the Sun disappeared we wouldn't see this for 8 minutes, i.e., speed of light, but that the Earth's orbit actually depends on where it is now - not 8 minutes ago. That if it depended upon where it was 8 minutes ago "it would be slung out of orbit in short order." Can someone explain how the Earth would be "slung out of orbit in short order?" I don't understand the reasoning or mechanics of why this would happen.

If the sun "vanished" instantly, the effect on the trajectory of planet Earth would have a direct effect on the planet at the speed of gravity. The speed of gravity doesn't necessarily have to be greater than the speed of light however. The lack of a "curvature" associated with the sun would have the effect of allowing the Earth to fly off on a tangent to it current circular path rather than to follow it's smooth curved path around the sun. Whether the effect would be "instant" or it's happens at the speed of light depends on the speed of gravity which does not *have* to be faster than C in EU/PC theory. It's more of a theoretical argument, one which ultimately depends on the speed of gravity.

[jacmac]

Michael said;

The speed of gravity doesn't necessarily have to be greater than the speed of light however.

I agree.
The sun cannot instantly vanish, or instantly appear. If things with mass cannot exceed the speed of light; that includes arriving or leaving. So I don't think the speed of gravity can be faster than that which provides gravity.

As to the waves, be they transverse, longitudinal, or vortex ring "waves," does not a wave need time to present itself as a wave ? You know, the up and down parts. An instant wave would have to have a frequency of infinity, no? If gravity is instantaneous then it is not a wave. IMO

Jack

[nick c]

I think that Bishop Sykes' example is based on the work of the late Tom Van Flandern.

It is my understanding that whether or not the Sun is capable of disappearing is not relevant to his argument. His point is that the Earth is orbiting a moving Sun and the information of where the Sun is going to be in the next instant has to be communicated (to the orbiting planet) at many times the speed of light. Van Flandern is not advocating instantaneity but rather speeds many times faster than light.

For those interested, here is a relevant article by Van Flandern (as noted by upriver earlier in this thread):
The Speed of Gravity - What the Experiments Say