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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" 1637 laughin 11-Feb-16 16:34
Re: gravity waves "detected" 614 Susan Doris 11-Feb-16 17:44
Re: gravity waves "detected" 502 Sirius7237 11-Feb-16 18:30
Re: gravity waves "detected" 603 laughin 11-Feb-16 21:20
Re: gravity waves "detected" 525 JonnyMcA 12-Feb-16 14:23
Re: gravity waves "detected" 560 laughin 12-Feb-16 15:51
Re: gravity waves "detected" 406 JonnyMcA 12-Feb-16 16:31
Re: gravity waves "detected" 513 laughin 13-Feb-16 18:26
Re: gravity waves "detected" 556 JonnyMcA 13-Feb-16 18:41
Re: gravity waves "detected" 638 Me 15-Feb-16 15:57
Re: gravity waves "detected" 474 laughin 15-Feb-16 20:17
Re: gravity waves "detected" 518 carolb 13-Feb-16 21:53
Re: gravity waves "detected" 411 D-Archer 14-Feb-16 11:16
Re: gravity waves "detected" 430 carolb 14-Feb-16 14:54
Re: gravity waves "detected" 422 Sirius7237 14-Feb-16 20:08
Re: gravity waves "detected" 523 carolb 14-Feb-16 22:31
Re: gravity waves "detected" 543 Aine 15-Feb-16 16:20
Re: gravity waves "detected" 462 D-Archer 15-Feb-16 09:59
Re: gravity waves "detected" 447 JonnyMcA 12-Feb-16 14:31
Re: gravity waves "detected" 476 carolb 13-Feb-16 21:29
Re: gravity waves "detected" 392 laughin 14-Feb-16 15:19
Re: gravity waves "detected" 337 skakos 15-Feb-16 14:07
Re: gravity waves "detected" 425 Pete Vanderzwet 11-Feb-16 21:06
Re: gravity waves "detected" 546 JonnyMcA 12-Feb-16 14:38
Onto Dark Energy waves! 483 Eddie Larry 11-Feb-16 21:34
It took 100 years to discover what Einstein already knew 336 David L 12-Feb-16 12:50
Re: It took 100 years to discover what Einstein already knew 429 Spiros 12-Feb-16 17:09
Re: It took 100 years to discover what Einstein already knew 491 D-Archer 15-Feb-16 12:47
Re: It took 100 years to discover what Einstein already knew 502 Aine 15-Feb-16 16:15
Re: It took 100 years to discover what Einstein already knew 454 D-Archer 15-Feb-16 18:53
Re: It took 100 years to discover what Einstein already knew 475 laughin 15-Feb-16 20:39
Re: It took 100 years to discover what Einstein already knew 412 Aine 16-Feb-16 01:48
Re: gravity waves "detected" 537 dong 12-Feb-16 18:36
Re: gravity waves "detected" 534 laughin 13-Feb-16 03:26
Re: gravity waves "detected" 459 dong 16-Feb-16 07:41
Liego 449 laughin 15-Feb-16 04:17
Gravity Waves of Propaganda the Sequel 444 D-Archer 15-Feb-16 09:48
Re: gravity waves "detected" 536 skakos 15-Feb-16 12:58
Re: gravity waves "detected" 493 Aine 15-Feb-16 22:31
Re: gravity waves "detected" 363 carolb 16-Feb-16 00:57
Re: gravity waves "detected" 438 D-Archer 16-Feb-16 11:47
Re: gravity waves "detected" 583 carolb 16-Feb-16 12:32
Re: gravity waves "detected" 393 D-Archer 16-Feb-16 14:13
Re: gravity waves "detected" 405 carolb 16-Feb-16 14:42
Re: gravity waves "detected" 376 D-Archer 16-Feb-16 15:17
Re: gravity waves "detected" 515 carolb 16-Feb-16 16:27
Re: gravity waves "detected" 521 D-Archer 17-Feb-16 14:08
Really? 410 Sirfiroth 17-Feb-16 15:11
Re: Really? 521 JonnyMcA 17-Feb-16 15:32
Re: Really? 512 D-Archer 17-Feb-16 15:42
Re: gravity waves "detected" 508 carolb 17-Feb-16 18:05
mods! 461 D-Archer 18-Feb-16 11:13
Re: mods! 544 carolb 18-Feb-16 14:14
Re: mods! 550 D-Archer 18-Feb-16 16:02
Re: gravity waves "detected" 628 Sirfiroth 17-Feb-16 01:06
Re: gravity waves "detected" 443 Aine 17-Feb-16 14:48
Re: gravity waves "detected" 494 JonnyMcA 17-Feb-16 15:19
Re: gravity waves "detected" 374 Sirfiroth 17-Feb-16 15:39
Re: gravity waves "detected" 465 JonnyMcA 17-Feb-16 17:37
Re: gravity waves "detected" 540 Aine 17-Feb-16 18:49
Re: gravity waves "detected" 483 laughin 16-Feb-16 20:24
Re: gravity waves "detected" 330 D-Archer 17-Feb-16 16:23
Gravy Waves 651 D-Archer 20-Feb-16 11:39
Playing devil’s advocate on the discovery of gravitational waves 594 laughin 02-Mar-16 18:23
Scientists: we're 100% convinced 423 laughin 07-Mar-16 17:13
Black holes and big bangs can't co-exist 513 laughin 13-Mar-16 04:52
Re: gravity waves "detected" 456 Observer 20-Apr-16 23:42
Re: gravity waves "detected" 461 laughin 21-Apr-16 14:02
Re: gravity waves "detected" 378 OCaptain 10-May-16 12:45
Re: gravity waves "detected" 373 laughin 10-May-16 13:16
Re: gravity waves "detected" 393 OCaptain 10-May-16 13:21
Re: gravity waves "detected" 445 laughin 10-May-16 19:25
Re: gravity waves "detected" 560 OCaptain 10-May-16 22:56
Re: gravity waves "detected" 463 laughin 11-May-16 15:32
Re: gravity waves "detected" 574 JonnyMcA 11-May-16 16:53
Re: gravity waves "detected" 557 laughin 12-May-16 16:26
pompousness "detected" 495 laughin 18-May-16 15:25
bump- 2 weeks 594 laughin 27-May-16 15:02
Re: bump- 3 weeks 537 laughin 02-Jun-16 23:20
Re: bump- 4 weeks and why isn't Carolb patrolling the threads 520 laughin 10-Jun-16 15:42
Gravitational Waves from Black Hole Megamergers Are Weaker Than Predicted 497 laughin 04-May-16 13:15
Re: Gravitational Waves from Black Hole Megamergers Are Weaker Than Predicted 511 D-Archer 09-May-16 19:05
Re: Gravitational Waves from Black Hole Megamergers Are Weaker Than Predicted 341 OCaptain 10-May-16 12:46
Re: Gravitational Waves from Black Hole Megamergers Are Weaker Than Predicted 543 laughin 10-May-16 13:27
Re: Gravitational Waves from Black Hole Megamergers Are Weaker Than Predicted 385 OCaptain 10-May-16 16:39
Re: Gravitational Waves from Black Hole Megamergers Are Weaker Than Predicted 441 laughin 10-May-16 19:10
how many times can you change the rules and still get a black hole 431 laughin 08-Jun-16 14:00
LIGO press conf, June 15 469 Observer 15-Jun-16 11:53
Re: LIGO press conf, June 15 453 D-Archer 15-Jun-16 14:48

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