Einstein's theory says the latter, is there proof or is it still hypothetical?

yayacatfight,

Does gravity act instantly or at c?
Einstein's theory says the latter, is there proof or is it still hypothetical?

Actually I think you will get a mixed bag of responses here.

#1 - There are those that go with Einstien and say "c". There has even been recent claims about a test that proved it was "c". But that test is being heavily refuted by many.

#2 - There are some that will say it is instantaneous and will show you mathematically the the rays of the sun are angled on reaching earth to a position that represents where the sun and earth aligned 8.5 minutes ago but that gravity ppoints toward the sun itself, hence the instaneous view.

#3 - And finally there will be those that claim there is no SOG (Speed of Gravity) that nothing is moving, it is all geometry and curved space.

Of the three I like #2 myself because it is based more on observation and seems to have a physical underpinning. It is as though gravity may be related to the particle entanglement process. But at this juncture there is no clear winner in this debate.

Originally posted by yayacatfight
Einstein's theory says the latter, is there proof or is it still hypothetical?

watch out for crackpots, kid!

ok. so yeah, a few months ago there was an experiment that claimed to have measured the speed of gravity as c. it was hotly disputed, and i never heard the final verdict.

so no, the speed of gravity hasn t been directly measured, it is still a theoretical result. however i should add that the theory that predicts this theoretical result is well tested experimentally. it s not proof, but it is very strong support of the fact the speed of gravity is c.

MacM: you know the rules. unless he asks for alternative answers, you keep your lid closed.

#2 - There are some that will say it is instantaneous and will show you mathematically the the rays of the sun are angled on reaching earth to a position that represents where the sun and earth aligned 8.5 minutes ago but that gravity ppoints toward the sun itself, hence the instaneous view.

This is interesting, and how I feel it should be, however ignorant I am.

MacM: Can you point me to somewhere I may read more about this experiment?

Thanks

Originally posted by yayacatfight
#2 - There are some that will say it is instantaneous and will show you mathematically the the rays of the sun are angled on reaching earth to a position that represents where the sun and earth aligned 8.5 minutes ago but that gravity ppoints toward the sun itself, hence the instaneous view.

This is interesting, and how I feel it should be, however ignorant I am.

MacM: Can you point me to somewhere I may read more about this experiment?

Thanks

hey, yayacatfight, don t listen to this guy, MacM, he s a crackpot, and he s wrong! gravity is not instantaneous!

yayacatfight,

Here is some of the debate.


http://www.space.com/scienceastronomy/gravity_speed_030116.html


This one is one of the more vocal ones but there are plenty that agree with him. Just as I am not liked here, he is generally not liked in the community but he is a qualified scientist with a long track record. He is the one that puts a speed on it of several billion c.


http://www.metaresearch.org/cosmology/speed_of_gravity.asp

All in all just type "speed of gravity" into search and surf. There are tons of sites most are about the recent experiment but there are plenty of sites that run counter to that.



lethe,


PS: I do believe I qualified the general views in the scientific community. I qualified my preference, just as you qualify your preference for Relativity.

If you read his question properly he is questioning if Einstien was right and SOG = c. How do you propose to answer him fully if you don't tell him the options?

Is this site strictly Einstein only? I thought it was about truth and education. Your attitude belongs in a book burning club.

This is not my theory. It is theories that are seriously considered in the scientific community.


************************

yayacatfight,

Was your question "How Einstein justified SOG = c?" or was it more "Is Einstein right that sog = c?". I took your question as the later.

Personal request here. When you have digested these links, please come back and report your feelings on this issue and the meaning of your question. And if you see members here trying to censor anything non-Einstein in nature.

.

I do appreciate the warning lethe, but I can draw my own conclusions. Please point me somewhere specific where I can read what the non-crackpots think.

Remember, among the crackpots of today are the geniuses of tomorrow. This is not a commentary on MacM specifically, but you have got to keep an open mind, otherwise it's a difficult walk back after choosing the wrong path.

There is no question that Einstein's theory holds up well observationially and experimentally. But one day, it will be proven incomplete, and rewritten. Of this, I am certain, just ask Newton. And it's very likely the person that rewrites the current theory will be considered a crackpot in his own lifetime.

Originally posted by yayacatfight
I do appreciate the warning lethe, but I can draw my own conclusions. Please point me somewhere specific where I can read what the non-crackpots think.

Remember, among the crackpots of today are the geniuses of tomorrow. This is not a commentary on MacM specifically, but you have got to keep an open mind, otherwise it's a difficult walk back after choosing the wrong path.

There is no question that Einstein's theory holds up well observationially and experimentally. But one day, it will be proven incomplete, and rewritten. Of this, I am certain, just ask Newton. And it's very likely the person that rewrites the current theory will be considered a crackpot in his own lifetime.

yeah. newton, poincaré, einstein, heisenberg, dirac, feynman, gell-mann, the list of crackpots that rewrote the theories of humanity goes on and on.... i guess the next theorist will be a crackpot in his own lifetime. i should give MacM and his crackpot companions more respect then, thanks for opening my eyes, yayacatfight.

good luck to you.

MacM: My question was a combination of both. I appreciate your answer and the links. And I will update you once I have digested enough on the subject. I do see an Einstein bias, but that's expected, I do not see censorship.

lethe: Where can you point me to convince me that I am foolish to believe that gravity may be instantaneous?

yayacatfight,

Thanks again. Your are right. As yet it hasn't come to censorship but the effort and intent is there. If I hadn't posted you most certainly would have only gotten the Einstein view and maybe, but not likely, a condensending comment about anyother view points.

Originally posted by yayacatfight
MacM: My question was a combination of both. I appreciate your answer and the links. And I will update you once I have digested enough on the subject. I do see an Einstein bias, but that's expected, I do not see censorship.

lethe: Where can you point me to convince me that I am foolish to believe that gravity may be instantaneous?

yayacatfight: ugh.

look, for a long time we thought that gravity was instantaneous. that theory is known as newtonian gravitation.

that theory is very good, but has certain shortcomings. it fails at certain predictions. a new theory came along which can predict everything the old theory can, and many more things, totally accurately. this new theory is called relativity, and it predicts the speed of gravity as c.

for you to believe gravity is instantaneous, is for you to take physics back 150 years, to a theory that has long since been disproved. while the rest of the world moves forward to new openminded ideas, you move backwards to ideas that were discarded centuries (i exaggerate a liitle) ago because they did not agree with experiment.

however, i never said you were foolish for thinking gravity is instantaneous. i made a sarcastic remark about your idea that tomorrow s geniuses are today s crackpots. i don t know where you got such an idea, because all of the great thinkers that i know of have been scientists, with mathematical and theoretical justifications for all their ideas, as well as predictions bourne up by experimental evidence, not crackpots. by definition, a crackpot is someone who lacks in mathematical and theoretical understanding, and has no experimental evidence to back himself up (among other things).

but who knows, maybe 400 yrs of tradition will be turned on its ear, and new science will start coming from crackpots.

Correct me if I am wrong, but there seems to be a misinterpretation about Einstein's predictions.

Gravity cannot act instantaneously in SR due to violation of casualty, but Einstein said nothing about the speed with which gravity acts In GR. His theory predicted that a DISTURBANCE in the gravitational field propogated at c. Here's the analogy.

Consider water in a pond. The molecules interact via a coulomb force which propogates at c. However if you drop a rock in a pond, the ripples (the disturbance) travels at a speed which is a function of the surface tension of the water and the density. The 2 speeds are different. However for gravitational fields it so happens that these 2 phenomena have the same propogation rate.

lethe: Yep, maybe I referred to crackpot using my own definition. What I meant was that it usually takes a while for an alternative theory to be accepted. All of Einstein's theory was not experimentally proven for quite some time, and in the interim, I am sure many people considered him a 'crackpot'.

Anyway, I am still waiting for you to provide me with a starting place so that I may convince myself. I admit I am ignorant on this subject, and I came here to learn. At least MacM provided me some links. You have in a nutshell just said, 'mostly everyone else thinks it, so should you'

Originally posted by yayacatfight
All of Einstein's theory was not experimentally proven for quite some time
Einstein's theory actually followed its experimental proof. Maxwell's equations, and the individual equations of Ampere, Gauss, and Farady, had all been experimentally tested for almost a century before Maxwell combined them together in one edifice. Relativity fell directly from it, as per Lorentz. In addition, the Michelson-Morley experiment was dying for a resolution. Einstein's theory immediately offered one.

I have no idea why so many people have this idea that relativity took a long time to gain acceptance. It's just some kind of common misconception -- a myth. It is true that some of Einstein's other work, such as the photoelectric effect, took a while to be accepted, but relativity was rather immediately and gratefully accepted.

- Warren

I thought Einstein's theory was only widely accepted after Eddington's eclipse experiment, 14 years later. Or am I mistaken?

Does anyone know a good place to go that summarizes the recent experiment regarding the galaxy that was eclipsed by Jupiter?

Originally posted by yayacatfight


Anyway, I am still waiting for you to provide me with a starting place so that I may convince myself. I admit I am ignorant on this subject, and I came here to learn. At least MacM provided me some links. You have in a nutshell just said, 'mostly everyone else thinks it, so should you'

i have no links to provide you. the simple answer is: learn the theories, and it will be obvious. but i have no shortcut for you to do so.

yayacatfight,

It was 14 years before Relativity gained great notariety. I made that same very point many months ago in a string I posted called "Trials of Einstein". This MSB didn't like it much.

As far as the test you inquire about it is part of the links I provided and as I said if you surf for "Speed of gravity" you get tons of them.

Originally posted by yayacatfight
I thought Einstein's theory was only widely accepted after Eddington's eclipse experiment, 14 years later. Or am I mistaken?
Depends on what you mean by 'widely.' Certainly, Eddington's experiment was one of the most beautiful tests of the new theory, but it wasn't a "revolutionary" theory -- just an "evolutionary" one. Relativity was required by Maxwell's equations -- unless you discard the very basic scientific premise that the laws of physics work the same way everywhere in the universe.

In addition, as has been mentioned many times, much of relativity theory was already stumbled upon by Lorentz, Poincare, and others long before Einstein had his aha moment.

- Warren

Originally posted by MacM
It was 14 years before Relativity gained great notariety. I made that same very point many months ago in a string I posted called "Trials of Einstein". This MSB didn't like it much.
MacM, your source was downright wrong. The entire board agreed it was a load of horseshit. Let it go.

- Warren

chroot,

OK. I think I said that when I said the MSB didn't like it much but I just wondered where he got the same 14 year interval between 1905 and 1919.

I agree that pragmatically you are correct. The key players that really understood what he was saying did like it but I'm sorry it was some years and a major proof before he publically became accepted.

It is however, not an issue which I would want to argue about.

So does that make you wrong Mac. If so admit to it.

MacM: <i>#2 - There are some that will say it is instantaneous and will show you mathematically the the rays of the sun are angled on reaching earth to a position that represents where the sun and earth aligned 8.5 minutes ago but that gravity ppoints toward the sun itself, hence the instaneous view.</i>

Reply: <i>This is interesting, and how I feel it should be, however ignorant I am.</i>

It may be interesting, but it is also incorrect.

The gravitational "pull" of the sun on the Earth points to where we see the sun now, not to where it actually is now. The reason is complicated, but can be shown using general relativity.

James, what's up with this then?

http://www.ldolphin.org/vanFlandern/gravityspeed.html

"In electromagnetism, it is said that moving charges anticipate each other's linear motion, but not acceleration"

"Fact: Gravity Has No Aberration" `

Tom Van Fladern is a known kook.

- Warren

Originally posted by chroot
Tom Van Fladern is a known kook.

- Warren

In other words, you're saying that the gravitational pull is directed towards where the sun was 8.3 minutes ago and that does not make orbits unstable?

http://arxiv.org/PS_cache/gr-qc/pdf/9909/9909087.pdf


James:

"Although gravity propagates at the speed of light in general relativity, the expected aberration is almost exactly canceled."

ryans,

So does that make you wrong Mac. If so admit to it.



ANS: Actually NO and I had hoped to avoid another clash over an issue that really is not very important.

I just responded in a manner to offer maximum comfort to chroot, whom I actually believe is wrong on this issue.

I supplied historical information when that string was running. Now perhaps you would be so kind to provide historical information which shows my original string was in error. As I recall the responses were nothing but verbal, no documented back up.

This time lets do it right and lay documentation on the table.

Show me the overwhelming acceptance of Relativity from the get go. Go ahead, no lip service, show me your paper work. I showed paper work that I had posted from, show me yours.

Referring to the first link posted by AndersHermansson

No equations, No derivations, therefore philosophy not physics.

Certified Quack.

Originally posted by ryans
Referring to the first link posted by AndersHermansson

No equations, No derivations, therefore philosophy not physics.

Certified Quack.

Check out the following link!
The thing about the first link that interrests me is that the gravitational pull does not seem to have aberration. From what I understand GR properly describes this. I reacted mainly to that James said that gravity had the same aberration as light.

Consider water in a pond. The molecules interact via a coulomb force which propogates at c. However if you drop a rock in a pond, the ripples (the disturbance) travels at a speed which is a function of the surface tension of the water and the density. The 2 speeds are different. However for gravitational fields it so happens that these 2 phenomena have the same propogation rate.

ryans: Is it not possible then, that everything a human observes maybe restrained by the surface tension of spacetime, that is c, and that things can move faster than c, but not to a human observer in spacetime?

yayacatfight,



ryans: Is it not possible then, that everything a human observes maybe restrained by the surface tension of spacetime, that is c, and that things can move faster than c, but not to a human observer in spacetime?

ANS:I would agree with that view but others here (More knowledgable on the subject) will disagree (I think) with your statement.


The following link explains James R., statement in the third paragraph.

http://math.ucr.edu/home/baez/physics/Relativity/GR/grav_speed.html

The following link states "Peer Review Rejects SOG test findings"

http://www.astronomy.com/Content/Dynamic/Articles/000/000/001/199jpzqr.asp

Under the peer review system, Fomalont and Kopeikin's initial paper on measuring the speed of gravity has been rejected.

This rejection of the finding does not also support TVF's claim of SOG equal to billions of c.



This issue is far from resolved.

http://physics.about.com/library/weekly/aa011503a.htm

Moreover, a number of physicists have already published their counter arguments that, accuracy questions aside, this experiment was simply a measurement of the speed of light.

this post ^^^^ was much easier to read than your past ones. thanks.

On Radio Active Waves,

Thanks. Just trying to rehabilitate my reputation.:D

Just keep me straight.

yayacatfight

ryans: Is it not possible then, that everything a human observes maybe restrained by the surface tension of spacetime, that is c, and that things can move faster than c, but not to a human observer in spacetime?

Yes, everything we observe is confined within 4 dimensions, 3 spacial and 1 temporal. That does not mean that we cannot construct theories in higher dimensions, as has been done.

So I agree with you.

If you want my personal opinion, I cannot see how gravity can act at a speed of c, it must be greater. But I do not have evidence on this, or any plausible theory, so unlike other members of this forum, I am not going to argue against theories that predict many things, which also show the gravity acts at a speed c. So until someone either proves otherwise, or circumvents my concerns, gravity acts at a speed c.

ryans,

Your last post makes me proud of you. I don't think anybody here claims any specific solution but you and I actually agree on something, that could be dangerous.:D

The only difference we have here is I'm not waiting for somebodyelse. We are infact designing an instrument that will hopefully be able to make a direct comparison measurement of gravity and light orientation as part of our overall testing.

MacM: I have digested to my satisfaction numerous links I could find on the subject and I will start a new thread to discuss my feelings.

By the way, thanks everyone, this thread (all of it) led me to my next thought, which is all I was looking for.