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sjw40364
2011-Mar-31, 03:38 AM
The problem with the theory of Black holes leads us to the problem with the theory of gravity. According to SR (Special Relativity) nothing can travel faster than the speed of light in forward time. Yet clearly gravity does extend beyond the event horizon of a black hole, from which not even light itself can escape. Modern science tries to explain this away by saying that the space-time curvature was frozen into place before the star collapsed into a black hole. This idea cannot stand as if the black hole moves, what causes the frozen space-time to move with it? What updates the space-time curvature when the black hole changes locations in space? If it was static then any changes in the black hole, such as size or location, would not be updated in the space-time curvature. What prevents light from escaping if the gravity field is only equivalent to what it was the instant before the star collapsed into a black hole? That theory ignores causality as then one would have to realize that gravity must indeed travel faster than light falsifying SR. I will not even get into the problems aberration and transit delay would cause in this post. But to answer the original post it is assumed that the matter is collapsed into a infinitesimal size. Unlike the 2 dimensional representations depicted that look whirlpool like you have to think 3 dimensionally. The black hole would pull equally from all points in space, think of an asteroid falling into earth's gravitational field, that is a more apt representation than the flat whirlpool analogy.

captain swoop
2011-Mar-31, 07:52 AM
sjw40364 Welcome to BAUT. You have posted in the Q&A Forum. this is reserved for questions and answers on the Mainstream of science. IFyou want to present ideas that are againstthe Mainstream then please do it in the Against the Mainstream Forum.

Please take some time to read the rules for posting and advice for posters. Theyare linked at the bottom of this post.

Hornblower
2011-Mar-31, 11:25 AM
The problem with the theory of Black holes leads us to the problem with the theory of gravity. According to SR (Special Relativity) nothing can travel faster than the speed of light in forward time. Yet clearly gravity does extend beyond the event horizon of a black hole, from which not even light itself can escape. Modern science tries to explain this away by saying that the space-time curvature was frozen into place before the star collapsed into a black hole. This idea cannot stand as if the black hole moves, what causes the frozen space-time to move with it? What updates the space-time curvature when the black hole changes locations in space? If it was static then any changes in the black hole, such as size or location, would not be updated in the space-time curvature. What prevents light from escaping if the gravity field is only equivalent to what it was the instant before the star collapsed into a black hole? That theory ignores causality as then one would have to realize that gravity must indeed travel faster than light falsifying SR. I will not even get into the problems aberration and transit delay would cause in this post. But to answer the original post it is assumed that the matter is collapsed into a infinitesimal size. Unlike the 2 dimensional representations depicted that look whirlpool like you have to think 3 dimensionally. The black hole would pull equally from all points in space, think of an asteroid falling into earth's gravitational field, that is a more apt representation than the flat whirlpool analogy.

Special relativity is valid only locally in a non-accelerated frame of reference where gravitational effects are negligible. To handle the analysis of a black hole we need the full-blown general relativity (GR). That is taking it to the next mathematical level, or perhaps several levels. After presenting SR, Einstein worked for ten years to master the necessary mathematical techniques before presenting GR. All of this was after he had earned his Ph.D. in physics.

The modern science, including GR, does not merely try to explain the workings of a black hole. It is highly successful. Since I am too rusty on the math to explain it reliably, I will leave it to those who are conversant in it, of whom there are several in this forum.

Among the occupational hazards for novices is bad writing on these topics by some in the popular media.

WayneFrancis
2011-Mar-31, 12:17 PM
The problem with the theory of Black holes leads us to the problem with the theory of gravity. According to SR (Special Relativity) nothing can travel faster than the speed of light in forward time. Yet clearly gravity does extend beyond the event horizon of a black hole, from which not even light itself can escape. Modern science tries to explain this away by saying that the space-time curvature was frozen into place before the star collapsed into a black hole. This idea cannot stand as if the black hole moves, what causes the frozen space-time to move with it? What updates the space-time curvature when the black hole changes locations in space? If it was static then any changes in the black hole, such as size or location, would not be updated in the space-time curvature. What prevents light from escaping if the gravity field is only equivalent to what it was the instant before the star collapsed into a black hole? That theory ignores causality as then one would have to realize that gravity must indeed travel faster than light falsifying SR. I will not even get into the problems aberration and transit delay would cause in this post. But to answer the original post it is assumed that the matter is collapsed into a infinitesimal size. Unlike the 2 dimensional representations depicted that look whirlpool like you have to think 3 dimensionally. The black hole would pull equally from all points in space, think of an asteroid falling into earth's gravitational field, that is a more apt representation than the flat whirlpool analogy.

Wow...this is so wrong...Where did you hear this? Bad sound bites in a popular science mag?

The reason a black hole has gravity is the same reason the electromagnetic force does. The virtual photons that carry this information is not subject to the same rules as normal particles. Thus the information of electric charge and gravity can be sensed by the rest of the universe. It is not thought that the black hole is frozen. It is not unchanging. A black hole with a charge will loose that charge very quickly as it attracts particles with the opposite charge until it becomes neutral. If the black hole where "froozen" as you describe then the charge would never change. neither would its mass and, like you pointed out, its location.

sjw40364
2011-Apr-03, 02:39 AM
Yes, but according to GR it is the space-time curvature which causes gravity, not the mass that causes space-time to curve. Yet GR says updates to the space-time curvature occur at the speed of c, ignoring aberration (an impossibility in itself). Now you may want to change what GR says causes gravity, but either GR is correct or it isn't. For the sake of this thread I will assume it is and that it is the space-time curvature that causes gravity and that it updates at the speed of c. Since we have not directly observed a black hole and can only assume they exist due to light curvature and x-ray data, what causes their gravity is anyone's guess, any theory is as valid as any other when it comes to untested theories. It would be equally valid to assume that gravity propagates at faster than c speeds or that the space-time curvature does, but since that would go against SR one cannot even contemplate such a thing in today's scientific world. And then that brings up the question of how this supposed space-time which is not an aether (but is actually composed of nothing) is affected by a mass which in turn causes gravity. Yet it must be composed of something if it was created at the moment of the BB, to expand, and to be affected by mass. And let's not talk about E = mc2, because if you actually realize what it says it says that m depends on energy (on velocity) and the photon has mass. Of course E = mc2 is not the equation Einstein originally wrote. His original equation was E subscript 0 = mc2 which says that m is constant and the photon is mass less.

pzkpfw
2011-Apr-03, 04:41 AM
Posts above this were moved from a Q&A thread: http://www.bautforum.com/showthread.php/114107-I-have-some-questions-about-blackholes...

A note to sjw40364: please keep non mainstream interpretations out of Q&A threads.

A note to everybody else: please don't reply to ATM posted in Q&A. (That leads to the question "why wasn't that post moved out then", to which the answer is basically that we try to mess with threads as little as possible. After Captain Swoops message, it should have just been dropped.)

pzkpfw
2011-Apr-03, 04:50 AM
... Since we have not directly observed a black hole and can only assume they exist due to light curvature and x-ray data, what causes their gravity is anyone's guess, any theory is as valid as any other when it comes to untested theories. ...

This kind of comment really confuses me.

Black holes were predicted by the relevant math. (And the "cause" was part of that: the mass of the black hole (and size it's packed in to)).

Any observations that followed, confirmed those predictions.

Comments like that bit I quoted seem to imply that "something was seen", and a theory called "Black Holes" was concocted to explain it. That seems back-to-front in regards to the actual sequence of events.

sjw40364, is that what you intended?

macaw
2011-Apr-03, 06:01 AM
The problem with the theory of Black holes leads us to the problem with the theory of gravity. According to SR (Special Relativity) nothing can travel faster than the speed of light in forward time. Yet clearly gravity does extend beyond the event horizon of a black hole, from which not even light itself can escape

Q1: So, where do you see a contradiction?



Modern science tries to explain this away

Q2: Modern science "tries" to explain what "away"?





What prevents light from escaping if the gravity field is only equivalent to what it was the instant before the star collapsed into a black hole?

No, what prevents it is the fact that escape velocity, at the even horizon, equals the speed of light.

Q3: Can you prove the above? (the math is trivial).






That theory ignores causality as then one would have to realize that gravity must indeed travel faster than light falsifying SR.

Nope.

Shaula
2011-Apr-03, 07:18 AM
E=mc2 says nothing about the mass of a photon. E0 is the rest mass, that is all. The full equation has a momentum term in it too which accounts for the photon's energy. Gravity works on mass-energy, not just mass.

You appear to be trying to falsify GR/SR using some rather basic verbal logic paradoxes (that are not all that paradoxical as they are largely based on misunderstanding the whole theory and picking bits to try to discredit). How do you account for the huge numbers of successful observations and predictions GR does cover? And perhaps more importantly do you think that in the hundred years since it was published no one has ever thought "hey, if gravity propagates at c then it gets trapped by a black hole!". Because they have. And doing the maths has so far always favoured GR over other theories.

sjw40364
2011-Apr-03, 10:22 PM
Energy E = the mass of an object times the square of the speed of light. There can only be one conclusion, that the photon or the energy it emits is a relation of its mass times the square of light, therefore the photon HAS mass. E0 = mc2 says that the rest energy is its mass times the square of the speed of light. Since a photon does not exist at rest, but only in motion it has no rest energy and therefore no mass.

http://en.wikipedia.org/wiki/Invariant_mass
see references 2nd entry pdf

sjw40364
2011-Apr-03, 10:50 PM
I am not trying to discredit GR anymore than GR discredited Newtonian gravity. It added to the theory, not subtracted from it. All tests that favor SR also favor LR equally, although at the time it was not thought to do so, but now we know that they do not favor one over the other. So we must now ask ourselves if any current tests favor one over the other.

(1) a modern updating of the classical Laplace experiment based on the absence of any change in the angular momentum of the Earth's orbit (a necessary accompaniment of any propagation delay for gravity even in a static field);
(2) an extension of this angular momentum argument to binary pulsars, showing that the position, velocity, and acceleration of each mass is anticipated in much less than the light-time between the masses;
(3) a non-null three-body experiment involving solar eclipses in the Sun-Earth-Moon system, showing that "optical" and "gravitational"Ě eclipses do not coincide;
(4) planetary radar ranging data showing that the direction of Earth's gravitational acceleration toward the Sun does not coincide with the direction of arriving solar photons;
(5) neutron interferometer experiments, showing a dependence of acceleration on mass, and therefore a violation of the weak equivalence principle (the geometric interpretation of gravitation); [2]
(6) the Walker-Dual experiment, showing in theory that changes in both gravitational and electrostatic fields propagate faster than the speed of light, c, a result reportedly given preliminary confirmation in a laboratory experiment.

To these, we can now add:

(7) An earlier laboratory experiment ([3], with summary description in [4]) showed that charges respond to each others instantaneous positions, and not to the "left-behind potential hill"Ě, when they are accelerated. This demonstrates that electrodynamic forces must likewise propagate at faster than light-speed more convincingly than earlier experiments showing angular momentum conservation.
(8) A new laboratory experiment at the NEC Research Institute in Princeton claims to have achieved propagation speeds of 310 c. [5] This supplements earlier quantum tunneling experiments. [6] It is still debated whether these experiment types using electromagnetic radiation can truly send information faster than light. [7] Whatever the resolution of that matter, the leading edge of the transmission is an electromagnetic wave, and therefore always travels at light-speed. However, such experiments have served to raise public consciousness about the faster-than-light-propagation concept.

Of all these experiments, #(2) -- the binary pulsars -- places the strongest lower limit to the speed of gravity: 2x1010 c.

Currently all observations and tests favor the interpretation of LR over SR, that the gravitational force propagates at faster than c speeds.
To date only one paper announced on 2003/01/08 by S. Kopeikin has tried to show that gravitational force propagates at the speed of c. Yet he found it necessary to revise his formula AFTER the results came in from his previously published formula so that they would match the data. It was found later that he did not measure gravity, but only the speed of light.
http://arxiv.org/abs/astro-ph/0301145
After being rejected for publication due to not passing peer review he restyled it as "a measurement of the deflection of a light signal by Jupiter" and published.

Only untested theories show that the gravitational force propagates at the speed of c, while all observational data and tests to date show that it propagates at faster than c, favoring LR over SR.
Even GR which states that space-time updates at the speed of c uses aberration set to 0, effectively adopting an instantaneous propagation speed to the gravitational force. Like light, if the gravitational force took 8.3 minutes to reach the earth from the Sun, aberration would be induced, yet GR sets aberration to 0 meaning that it must propagate at faster than c speeds else aberration would be >0.

macaw
2011-Apr-04, 03:00 AM
(6) the Walker-Dual experiment, showing in theory that changes in both gravitational and electrostatic fields propagate faster than the speed of light, c, a result reportedly given preliminary confirmation in a laboratory experiment.

Q5: Reference, please. Was it published in a peer-reviwed journal?





(7) An earlier laboratory experiment ([3], with summary description in [4]) showed that charges respond to each others instantaneous positions, and not to the "left-behind potential hill"Ě, when they are accelerated. This demonstrates that electrodynamic forces must likewise propagate at faster than light-speed more convincingly than earlier experiments showing angular momentum conservation.

Q6: Reference, please.



(8) A new laboratory experiment at the NEC Research Institute in Princeton claims to have achieved propagation speeds of 310 c.

Q7: Yes, this experiment is known. What sort of velocity was being measured? Was it group or phase velocity? What isthe difference between the two velocities?





[5] This supplements earlier quantum tunneling experiments. [6] It is still debated whether these experiment types using electromagnetic radiation can truly send information faster than light. [7] Whatever the resolution of that matter, the leading edge of the transmission is an electromagnetic wave, and therefore always travels at light-speed. However, such experiments have served to raise public consciousness about the faster-than-light-propagation concept.

Q8: Reference , please.




Of all these experiments, #(2) -- the binary pulsars -- places the strongest lower limit to the speed of gravity: 2x1010 c.

Ah, you are copying and pasting from the MetaResearch page of the now defunct Tom van Flandern.




Currently all observations and tests favor the interpretation of LR over SR, that the gravitational force propagates at faster than c speeds.

Q9: What is "LR"?



To date only one paper announced on 2003/01/08 by S. Kopeikin has tried to show that gravitational force propagates at the speed of c. Yet he found it necessary to revise his formula AFTER the results came in from his previously published formula so that they would match the data. It was found later that he did not measure gravity, but only the speed of light.
http://arxiv.org/abs/astro-ph/0301145

This doesn't change anything, GR predicts that gravitational waves propagate at c.

Q10: Do you know of any experiment falsifying GR?





Only untested theories show that the gravitational force propagates at the speed of c, while all observational data and tests to date show that it propagates at faster than c, favoring LR over SR.

Q11: Prove it.



Even GR which states that space-time updates at the speed of c uses aberration set to 0,

Q12: Really? What book or paper did you read that?

macaw
2011-Apr-04, 03:03 AM
Energy E = the mass of an object times the square of the speed of light. There can only be one conclusion, that the photon or the energy it emits is a relation of its mass times the square of light, therefore the photon HAS mass.

Q13: Yet, experiments falsify your statement. How do you explain that?



E0 = mc2 says that the rest energy is its mass times the square of the speed of light. Since a photon does not exist at rest, but only in motion it has no rest energy and therefore no mass.

Q14: So, you are contradicting yourself. You claimed the opposite in the preceding sentence.

Tensor
2011-Apr-04, 03:15 AM
Energy E = the mass of an object times the square of the speed of light. There can only be one conclusion, that the photon or the energy it emits is a relation of its mass times the square of light, therefore the photon HAS mass.

No, go look at your link again. Before you even get to rest mass. The first entry is particle physics. The equation there is (m0c2)2 = E2 - ||pc||2. Rearranging, you get E2=(m0c2)2 + ||pc||2

Note the p term. That term is momentum. A photon has momentum. So the total energy of a photon is the square root of it's rest mass, squared, (which is zero) plus it's momentum times the speed of light, squared.


E0 = mc2 says that the rest energy is its mass times the square of the speed of light. Since a photon does not exist at rest, but only in motion it has no rest energy and therefore no mass.

That's correct. If you look at the equation above again, you will see that in a rest frame, the momentum is zero. That leaves E2=(m0c2)2. If you take the square root of both sides you get E = m0c2. Funny how that works, eh?

Recapping for you. In motion, the equation to use is E2=(m0c2)2 + ||pc||2. In the rest fram, the equation is E = m0c2

Cavorite
2011-Apr-04, 05:32 AM
What prevents light from escaping if the gravity field is only equivalent to what it was the instant before the star collapsed into a black hole?

What stops it escaping is the fact that the mass of the star has been packed down into a much smaller space, and that gravitational acceleration varies as the inverse square. Light can escape from a black hole at distances greater than the event horizon.

Turning a star into a black hole doesn't increase the gravitational pull in any way - if the sun was turned into a black hole then we would continue to orbit just as we always have. The mass hasn't changed, nor has the distance from the center of mass, so there's no change in the pull felt. But the radius of the sun would now be about 3km instead of 695,000km, so the force felt close to the surface is substantially higher. Light emitted from out here near the Earth will "escape" just fine, whether we are orbiting our regular sun or the equivalent mass black hole.

Shaula
2011-Apr-04, 06:59 AM
If you are talking about Lorentzian relativity doesn't the minor fact that it predicts the wrong rate of precession for Mercury hinder it?

GR predictions work for close binary pulsars giving an accuracy of a couple of percent on the speed of gravity. Where did you get 2020c from that?

John Mendenhall
2011-Apr-04, 02:21 PM
Go back and read Mr. Hornblower's post #3 in this thread. GR (not SR) makes all the relevant predictions. There are many discussions about this on UT threads. Got a good GPS unit? It knows where you are within a foot or so by applied GR. Review the math replies above. You are making some untoward assumptions about GR and SR.

John Mendenhall
2011-Apr-04, 02:24 PM
Ah, that's intended for the OP, sorry, Shaula, it reads like I'm replying to you
.

caveman1917
2011-Apr-04, 07:12 PM
Modern science tries to explain this away by saying that the space-time curvature was frozen into place before the star collapsed into a black hole.

The spacetime curvature being spoken of as "frozen" around the event horizon is not meant to be taken as you do. The operational definition of a black hole is the spacetime curvature outside of the EH. In that sense it is "frozen", not in the completely frozen sense you take it to be. For example, when a particle falls in, you can consider it as leaving its mass-energy effect (spacetime curvature) "behind" as it crosses the EH (adding to and changing the BH curvature). The same for a charged particle leaving its electric charge behind.

It is frozen in the sense that whatever happens to the particle once inside the event horizon doesn't matter squat anymore, it is for all intents and purposes "frozen" within the outside curvature the moment it passes the EH.

Tensor
2011-Apr-05, 03:26 AM
All tests that favor SR also favor LR equally, although at the time it was not thought to do so, but now we know that they do not favor one over the other. So we must now ask ourselves if any current tests favor one over the other.

Ya might want to define LR. Is it Lorentzian Relativity or something from Laplace?


(1) a modern updating of the classical Laplace experiment based on the absence of any change in the angular momentum of the Earth's orbit (a necessary accompaniment of any propagation delay for gravity even in a static field);

Ahhhhh, but there is. Itís not a case of an absence of the change, itís a case of the change being so small as to not be able to be measured. The Equation for this is dr/dt which equals (64/5)(G3/c5)((m1m2)(m1+m2))/r3. Where m1 is the mass of the sun,
m2 is the mass of the Earth, r is the distance between the earth and the sun, G is gravitational constant and c is, of course, the speed of light.

Saving all of you the trouble of calculating it ( Calculating the problems are optional. The equations can be found in Chapter 36 of MTW) you end up with the Earth losing approx 3.5 x 10-13 m per year to its orbit (~200 w of power). Feel free to explain to us how you would measure that amount of loss of angular momentum over Earthís orbit in a year.


(2) an extension of this angular momentum argument to binary pulsars, showing that the position, velocity, and acceleration of each mass is anticipated in much less than the light-time between the masses;

Of course it is. That's how General Relativity (GR) works. Or didn't you know that? But, you missed one, the change in acceleration is also a component of gravity. So, here you go. While gravitational effects and gravitational radiation move at c, and the vectors should point at the retarded positions of the sources, the radiative terms in GR cause the vector to point more toward the instantaneous position, giving the appearance that effects are moving faster than c.

EM forces, which we know propagate at the speed of light, also point to the retarded position, with radiative corrections . EM accounts for the velocity of the source. If, the EM force ďmissesĒ the velocity, the system radiates. Gravity does the same thing, but at a different level. It addition to the velocity, it also account for the acceleration of the source. For EM, the radiation term goes as (v/c)3 and for gravity the additional term is (v/c)5. Which gives the impression that gravity is instantaneous.

The above is just a quick overview of the paper by Steve Carlip (http://arxiv.org/pdf/gr-qc/9909087v2) If you feel this answer is incorrect, it is my error, not his. Please feel free to point out, in the paper, what you specifically disagree with.

(3) a non-null three-body experiment involving solar eclipses in the Sun-Earth-Moon system, showing that "optical" and "gravitational" eclipses do not coincide;

See #2 Above.


(4)planetary radar ranging data showing that the direction of Earth's gravitational acceleration toward the Sun does not coincide with the direction of arriving solar photons;

See #2 Above.


(5)neutron interferometer experiments, showing a dependence of acceleration on mass, and therefore a violation of the weak equivalence principle (the geometric interpretation of gravitation); [2]

Please provide a citation for this experiment.


(6)the Walker-Dual experiment, showing in theory that changes in both gravitational and electrostatic fields propagate faster than the speed of light, c, a result reportedly given preliminary confirmation in a laboratory experiment.

Hold on, does the Walker-Dual experiment confirm the theory or not? Why another experiment? However, please provide a citation for both experiments, Also, See #2 above.


To these, we can now add:

An earlier laboratory experiment ([3], with summary description in [4]) showed that charges respond to each others instantaneous positions, and not to the "left-behind potential hill", when they are accelerated. This demonstrates that electrodynamic forces must likewise propagate at faster than light-speed more convincingly than earlier experiments showing angular momentum conservation.

By how much acceleration? How far behind? What experiment? Making wild claims doesnít cut it here. Citations, citations, citations.


A new laboratory experiment at the NEC Research Institute in Princeton claims to have achieved propagation speeds of 310 c. [5] This supplements earlier quantum tunneling experiments. [6] It is still debated whether these experiment types using electromagnetic radiation can truly send information faster than light.

Quantum Field Theory (QFT) does not make a claim to faster than light travel for information. QFT has Special Relativity built into it (including the c limit), or did you not know that?

Of all these experiments, #(2) -- the binary pulsars -- places the strongest lower limit to the speed of gravity: 2x1010 c.

And your citation for this claim is? If this is the case, exactly how do you explain the match of the observation of PSR 1913+16 (http://www.gw-indigo.org/tiki-read_article.php?articleId=13) to the prediction of GR, which uses the speed of gravity = c? How does your citation explain the observation?


Currently all observations and tests favor the interpretation of LR over SR, that the gravitational force propagates at faster than c speeds.

Nope, you havenít provided any support for this claim. Where are all your citations?


To date only one paper announced on 2003/01/08 by S. Kopeikin has tried to show that gravitational force propagates at the speed of c.

snip...

After being rejected for publication due to not passing peer review he restyled it as "a measurement of the deflection of a light signal by Jupiter" and published.

And so? He published what he though was support for the speed of gravity which turned out not to be support and was called on it. You donít seem to realize that the match of GR predictions to observations is support for gravity having a speed of c.


Only untested theories show that the gravitational force propagates at the speed of c, while all observational data and tests to date show that it propagates at faster than c, favoring LR over SR.

Are you seriously claiming that GR is untested? Did you do any research on this before posing the flat incorrect claims here?


Even GR which states that space-time updates at the speed of c uses aberration set to 0, effectively adopting an instantaneous propagation speed to the gravitational force. Like light, if the gravitational force took 8.3 minutes to reach the earth from the Sun, aberration would be induced, yet GR sets aberration to 0 meaning that it must propagate at faster than c speeds else aberration would be >0.

I donít know where you get that from. But, if you think so, it should be rather easy for you to show exactly where Carlip is wrong in the paper I linked to, right? So, Iíll be waiting for that.

John Mendenhall
2011-Apr-05, 10:11 PM
To the best of my knowledge, Tensor is correct.

OP, you need to have a clear understanding of GR, even if only at the non-mathematical level, before positing your ATM ideas. The blunder about speed of gravity is a serious one. IIRC, the problem (which Newton was aware of!) was not settled until Ol' Al developed GR.