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JonnyMcA Wrote:
> Hi Duane
> You are professing again that gravity is faster
> than light. It is not faster than light.
> Gravitational interactions between bodies is at
> the speed of light, and it doesn't matter how many
> times you assert it, it will not change the
> predictions of General relativity, which as we
> have seen has passed every test so far.


Tom Van Flandern

The most amazing thing I was taught as a graduate student of celestial mechanics at Yale in the 1960s was that all gravitational interactions between bodies in all dynamical systems had to be taken as instantaneous. This seemed unacceptable on two counts. In the first place, it seemed to be a form of “action at a distance”. Perhaps no one has so elegantly expressed the objection to such a concept better than Sir Isaac Newton: “That one body may act upon another at a distance through a vacuum, without the mediation of any thing else, by and through which their action and force may be conveyed from one to the other, is to me so great an absurdity, that I believe no man who has in philosophical matters a competent faculty of thinking, can ever fall into it.” (See Hoffman, 1983.) But mediation requires propagation, and finite bodies should be incapable of propagation at infinite speeds since that would require infinite energy. So instantaneous gravity seemed to have an element of magic to it.


The second objection was that we had all been taught that Einstein’s special relativity (SR), an experimentally well-established theory, proved that nothing could propagate in forward time at a speed greater than that of light in a vacuum. Indeed, as astronomers we were taught to calculate orbits using instantaneous forces; then extract the position of some body along its orbit at a time of interest, and calculate where that position would appear as seen from Earth by allowing for the finite propagation speed of light from there to here. It seemed incongruous to allow for the finite speed of light from the body to the Earth, but to take the effect of Earth’s gravity on that same body as propagating from here to there instantaneously. Yet that was the required procedure to get the correct answers.

These objections were certainly not new when I raised them. They have been raised and answered thousands of times in dozens of different ways over the years since general relativity (GR) was set forth in 1916. Even today in discussions of gravity in USENET newsgroups on the Internet, the most frequently asked question and debated topic is “What is the speed of gravity?” It is only heard less often in the classroom because many teachers and most textbooks head off the question by hastily assuring students that gravitational waves propagate at the speed of light, leaving the firm impression, whether intended or not, that the question of gravity’s propagation speed has already been answered.

Text Box: Figure 1. Orbits are unstable if forces propagate with finite speed.Yet, anyone with a computer and orbit computation or numerical integration software can verify the consequences of introducing a delay into gravitational interactions. The effect on computed orbits is usually disastrous because conservation of angular momentum is destroyed. Expressed less technically by Sir Arthur Eddington, this means: “If the Sun attracts Jupiter towards its present position S, and Jupiter attracts the Sun towards its present position J, the two forces are in the same line and balance. But if the Sun attracts Jupiter toward its previous position S’, and Jupiter attracts the Sun towards its previous position J’, when the force of attraction started out to cross the gulf, then the two forces give a couple. This couple will tend to increase the angular momentum of the system, and, acting cumulatively, will soon cause an appreciable change of period, disagreeing with observations if the speed is at all comparable with that of light.” (Eddington, 1920, p. 94) See Figure 1.

> You are again looking at it far too simply and
> expecting a simple truth to emerge, when the
> reality is a bit more complicated to try to
> picture or explain. As far as I understand it,
> the gravitational waves from black hole mergers do
> not originate from within the event horizons, but
> from the region of space outside it.

let's not get gravitation and gravitational waves mixed here
they are claiming that gravitation "energy" is being released
and this is somehow causing (mechanism?) the "rippling of space".
so the LIGO isn't measuring
the gravitation "force" of the black holes, but the indirect disturbance
of space caused by it.

Indeed, if
> the physics is the same with regards light, then
> any wave emitted, be it light or gravitational,
> from the event horizon or below, will be Doppler
> shifted to an infinitely large wavelength by the
> time it leaves the event horizon. And as any 1st
> year physics student will tell you, a "wave" with
> infinite wavelength is not waving, and so cannot
> propagate. If it cannot propagate, it does not
> travel through space. This is how light, which
> has no mass, cannot escape the event horizon of a
> black hole.

I have stated that it is "different" from light
and you even stated that it didn't have to be EM

Indeed if the physics is the same,
have they calculated the distortion
caused by "dark energy" stretching
that same space-time fabric/geometry between the black holes and Earth
1,000,000,000 light years apart?

> So how does gravity from inside the event horizon
> communicate with objects outside. Well, it is
> because the concentration of mass-energy inside
> the the event horizon curves space-time - BUT the
> event horizon marks the point where the curvature
> of space-time is infinite. Hence it is actually
> form the point just above the event horizon that
> communicates the gravitational field, not what is
> below. That is how gravity seemingly can escape a
> black hole. In General relativity, it is not
> escaping, but rather the mass is affecting
> space-time outside the event horizon which is what
> other bodies then react to.

"Infinities" should cause one to recheck their math

Once inside the "event horizon", mass, gravity and light
and their effects should disappear. so they shouldn't be
attracting anything or distorting space

so saying a black hole has "the mass of x thousands of suns"
is bogus because that mass is gone from our realm and shouldn't
have any affect on us.

How does the "mass" inside the black hole
"affect" space-time outside the event horizon?
by what mechanism?

another way to ask:
does mass warp space directly?
so is what we see as "gravity" is just the warping of space?

Or does mass give off a gravitational field
consisting of "gravitons" which interacts with
other bodies and space.

some things to think about in a non-confrontational way :)
remember how you felt when the "Santa Claus story" start to fall
apart due to the inconsistencies?

> Jonny

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Subject Views Written By Posted
gravity waves "detected" 1552 laughin 11-Feb-16 16:34
Re: gravity waves "detected" 562 Susan Doris 11-Feb-16 17:44
Re: gravity waves "detected" 452 Sirius7237 11-Feb-16 18:30
Re: gravity waves "detected" 554 laughin 11-Feb-16 21:20
Re: gravity waves "detected" 472 JonnyMcA 12-Feb-16 14:23
Re: gravity waves "detected" 510 laughin 12-Feb-16 15:51
Re: gravity waves "detected" 355 JonnyMcA 12-Feb-16 16:31
Re: gravity waves "detected" 459 laughin 13-Feb-16 18:26
Re: gravity waves "detected" 508 JonnyMcA 13-Feb-16 18:41
Re: gravity waves "detected" 573 Me 15-Feb-16 15:57
Re: gravity waves "detected" 425 laughin 15-Feb-16 20:17
Re: gravity waves "detected" 462 carolb 13-Feb-16 21:53
Re: gravity waves "detected" 360 D-Archer 14-Feb-16 11:16
Re: gravity waves "detected" 376 carolb 14-Feb-16 14:54
Re: gravity waves "detected" 372 Sirius7237 14-Feb-16 20:08
Re: gravity waves "detected" 475 carolb 14-Feb-16 22:31
Re: gravity waves "detected" 487 Aine 15-Feb-16 16:20
Re: gravity waves "detected" 412 D-Archer 15-Feb-16 09:59
Re: gravity waves "detected" 390 JonnyMcA 12-Feb-16 14:31
Re: gravity waves "detected" 429 carolb 13-Feb-16 21:29
Re: gravity waves "detected" 341 laughin 14-Feb-16 15:19
Re: gravity waves "detected" 282 skakos 15-Feb-16 14:07
Re: gravity waves "detected" 375 Pete Vanderzwet 11-Feb-16 21:06
Re: gravity waves "detected" 494 JonnyMcA 12-Feb-16 14:38
Onto Dark Energy waves! 436 Eddie Larry 11-Feb-16 21:34
It took 100 years to discover what Einstein already knew 290 David L 12-Feb-16 12:50
Re: It took 100 years to discover what Einstein already knew 380 Spiros 12-Feb-16 17:09
Re: It took 100 years to discover what Einstein already knew 443 D-Archer 15-Feb-16 12:47
Re: It took 100 years to discover what Einstein already knew 453 Aine 15-Feb-16 16:15
Re: It took 100 years to discover what Einstein already knew 404 D-Archer 15-Feb-16 18:53
Re: It took 100 years to discover what Einstein already knew 425 laughin 15-Feb-16 20:39
Re: It took 100 years to discover what Einstein already knew 366 Aine 16-Feb-16 01:48
Re: gravity waves "detected" 494 dong 12-Feb-16 18:36
Re: gravity waves "detected" 487 laughin 13-Feb-16 03:26
Re: gravity waves "detected" 409 dong 16-Feb-16 07:41
Liego 402 laughin 15-Feb-16 04:17
Gravity Waves of Propaganda the Sequel 394 D-Archer 15-Feb-16 09:48
Re: gravity waves "detected" 476 skakos 15-Feb-16 12:58
Re: gravity waves "detected" 442 Aine 15-Feb-16 22:31
Re: gravity waves "detected" 313 carolb 16-Feb-16 00:57
Re: gravity waves "detected" 393 D-Archer 16-Feb-16 11:47
Re: gravity waves "detected" 529 carolb 16-Feb-16 12:32
Re: gravity waves "detected" 345 D-Archer 16-Feb-16 14:13
Re: gravity waves "detected" 360 carolb 16-Feb-16 14:42
Re: gravity waves "detected" 333 D-Archer 16-Feb-16 15:17
Re: gravity waves "detected" 462 carolb 16-Feb-16 16:27
Re: gravity waves "detected" 470 D-Archer 17-Feb-16 14:08
Really? 363 Sirfiroth 17-Feb-16 15:11
Re: Really? 468 JonnyMcA 17-Feb-16 15:32
Re: Really? 458 D-Archer 17-Feb-16 15:42
Re: gravity waves "detected" 459 carolb 17-Feb-16 18:05
mods! 413 D-Archer 18-Feb-16 11:13
Re: mods! 495 carolb 18-Feb-16 14:14
Re: mods! 494 D-Archer 18-Feb-16 16:02
Re: gravity waves "detected" 575 Sirfiroth 17-Feb-16 01:06
Re: gravity waves "detected" 393 Aine 17-Feb-16 14:48
Re: gravity waves "detected" 437 JonnyMcA 17-Feb-16 15:19
Re: gravity waves "detected" 325 Sirfiroth 17-Feb-16 15:39
Re: gravity waves "detected" 401 JonnyMcA 17-Feb-16 17:37
Re: gravity waves "detected" 488 Aine 17-Feb-16 18:49
Re: gravity waves "detected" 436 laughin 16-Feb-16 20:24
Re: gravity waves "detected" 282 D-Archer 17-Feb-16 16:23
Gravy Waves 599 D-Archer 20-Feb-16 11:39
Playing devil’s advocate on the discovery of gravitational waves 543 laughin 02-Mar-16 18:23
Scientists: we're 100% convinced 368 laughin 07-Mar-16 17:13
Black holes and big bangs can't co-exist 467 laughin 13-Mar-16 04:52
Re: gravity waves "detected" 405 brett z 20-Apr-16 23:42
Re: gravity waves "detected" 413 laughin 21-Apr-16 14:02
Re: gravity waves "detected" 330 OCaptain 10-May-16 12:45
Re: gravity waves "detected" 296 laughin 10-May-16 13:16
Re: gravity waves "detected" 349 OCaptain 10-May-16 13:21
Re: gravity waves "detected" 394 laughin 10-May-16 19:25
Re: gravity waves "detected" 508 OCaptain 10-May-16 22:56
Re: gravity waves "detected" 408 laughin 11-May-16 15:32
Re: gravity waves "detected" 506 JonnyMcA 11-May-16 16:53
Re: gravity waves "detected" 506 laughin 12-May-16 16:26
pompousness "detected" 444 laughin 18-May-16 15:25
bump- 2 weeks 546 laughin 27-May-16 15:02
Re: bump- 3 weeks 485 laughin 02-Jun-16 23:20
Re: bump- 4 weeks and why isn't Carolb patrolling the threads 475 laughin 10-Jun-16 15:42
Gravitational Waves from Black Hole Megamergers Are Weaker Than Predicted 459 laughin 04-May-16 13:15
Re: Gravitational Waves from Black Hole Megamergers Are Weaker Than Predicted 466 D-Archer 09-May-16 19:05
Re: Gravitational Waves from Black Hole Megamergers Are Weaker Than Predicted 285 OCaptain 10-May-16 12:46
Re: Gravitational Waves from Black Hole Megamergers Are Weaker Than Predicted 495 laughin 10-May-16 13:27
Re: Gravitational Waves from Black Hole Megamergers Are Weaker Than Predicted 336 OCaptain 10-May-16 16:39
Re: Gravitational Waves from Black Hole Megamergers Are Weaker Than Predicted 390 laughin 10-May-16 19:10
how many times can you change the rules and still get a black hole 384 laughin 08-Jun-16 14:00
LIGO press conf, June 15 424 brett z 15-Jun-16 11:53
Re: LIGO press conf, June 15 410 D-Archer 15-Jun-16 14:48

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