Drunk on Black Holes

[imatfaal]

Where in any of those papers do the researchers claim that black holes do not exist?

 

My quick reading left me with impression they are working on the quantum mechanical unitary transformation at a very basic level of pre-black hole to black hole - this is very interesting but also presupposes that black holes are good theory (ie shown from a GR perspective) and something to investigate on a qm level.

 

You claimed that Penrose and Hawkings papers were flawed IIRC - that is pretty much attacking the GR basis of black holes. at least some of your criticisms seemed to be based on the use of a schwartzchild metric at the event horizon - this results in a completely bogus mathematical singularity as Spyman pointed out pages ago.

 

The model - for that is what a physical theory is - works at present; the formation of a black hole, the "stuff" that is beyond the event horizon, the details of h radiation, the information paradox etc all will have to wait for a valid theory that unifies qm and gravity, perhaps that unifies all 4 forces. The inability to explain deeper and more fundamental questions has never really been a problem for physical theories - do the observations match nature? are there any anomalies? do all prediction which flow from the theory work out? - then carry on using it till we gain more knowledge.

[decraig]

Where in any of those papers do the researchers claim that black holes do not exist?

 

My quick reading left me with impression they are working on the quantum mechanical unitary transformation at a very basic level of pre-black hole to black hole - this is very interesting but also presupposes that black holes are good theory (ie shown from a GR perspective) and something to investigate on a qm level.

 

You claimed that Penrose and Hawkings papers were flawed IIRC - that is pretty much attacking the GR basis of black holes. at least some of your criticisms seemed to be based on the use of a schwartzchild metric at the event horizon - this results in a completely bogus mathematical singularity as Spyman pointed out pages ago.

 

The model - for that is what a physical theory is - works at present; the formation of a black hole, the "stuff" that is beyond the event horizon, the details of h radiation, the information paradox etc all will have to wait for a valid theory that unifies qm and gravity, perhaps that unifies all 4 forces. The inability to explain deeper and more fundamental questions has never really been a problem for physical theories - do the observations match nature? are there any anomalies? do all prediction which flow from the theory work out? - then carry on using it till we gain more knowledge.

I don't know how to break-up a quote so I will refer to your comments by paragraph.

 

Par.1: They don't.

 

Par.2: I did not read-in this presupposition. In fact, they are aware that GR alone does not lead to an event horizon but would require something more than quantum tunneling. I did the math for a spherically symmetrical non-solution in post #29.

 

Par. 3: Penrose and Hawking gloss over formation, and continue forth as if it were established fact, or perhaps left it for others. This is what seems to have lead to general popular confusion and false claims.

 

I don't know what "bugus" means. The horizon would be what is called a "coordinate singularity where the metric tensor is not well defined." The designation 'coordinate' means that there exists at least one coordinate basis where the metric is well defined. This is unlike the central singularity which is not well defined in any coordinate system. If you want to see what this looks like go the the wiki for the Schwarztchild solution and set R_s=R.

 

Par. 4. No. The models are static solutions. Formation, using gr alone, would require a non-static solution.

Edited January 5, 2014 by decraig

[hoola]

so, no response to my previous posting (#34) as to black holes consisting of the "strings" of string theory as a minimum state of representation of the matter and energy that create the hole? Or that black holes are a recording device that can be read at some future point? Does not some information or energy get out through the event horizon? After all, gravity gets out......that is information or energy or whatever it is...... If gravity does not "get out" through the event horizon, then I suppose it's apparent appearance to the external universe is at the event horizon, not at the center of the black hole.....but averaged out over the radii of the black hole event horizon.....edd

Edited January 5, 2014 by hoola

[Strange]

so, no response to my previous posting (#34) as to black holes consisting of the "strings" of string theory

 

Like this: http://en.wikipedia.org/wiki/Fuzzball_%28string_theory%29 ?

[hoola]

funny idea, eh...even gravity cannot escape gravity ! I read the thread above and am delighted by the idea that hawking radiation might deliver a readout of the fuzzball string data. Wouldn't that mean that going out to a primordial black hole and reading the data encoded within, one could get a "reading" on the big bang that created said black hole giving us some details of the event ?

I am puzzled by gravity being associated with the center of the classic black hole....as stated above, if light cannot escape gravity, and light is a "thing", then how can gravity which is also a definable "thing" manage to escape the horizon? Even if gravity is not a "thing" in the classic sense, if light information cannot pass the swartzchild radius, might not this govern internal gravity information? To me, this would indicate that the gravity felt outside the event horizon is a "reflection" of the gravity force inside the horizon, not the force itself, in the "classic" black hole scenario. It does make sense that the "fuzzball" type of hole has a lower the internal density. As the volume of the hole increases, the internal density decreases. This seems to remove the "gravity can't escape itself" paradox as gravity was never infinte. If a "fuzzball" were the size of the universe, would the density drop down to what we perceive as the dark energy density? What would a universed-size fuzzball look like? Like what we are in?

Edited January 5, 2014 by hoola

[MigL]

What do you mean by 'gravity getting out of the black hole' or event horizon ?

Why do you assume gravity has to 'travel' to a location to affect said location ?

 

Gravity is the condition assumed by space-time in response to the presence of energy-momentum.

The fact that a black hole is there means space-time in its vicinity is distorted from flat into a curvature which we call gravity. It certainly does not radiate from the centre or the event horizon outwards. And yes, from the definition, even gravity would gravitate.

 

Are you proposing that there is another stable state at the Planck or string level so that we can avoid the singular state currently indicated by GR to be the final state of a collapsing large star ? In effect, there is no singularity at the centre of the event horizon, just extremely dense 'stringonium" ?

[decraig]

The purpose of this thread was to find experimental and theoretical support for black holes.

 

There are other threads about black holes where existence is not questioned.

 

Physical Evidence: So far, I have found no supporting arguments or references to arguments of support.

 

General Relativity: Inwardly falling uncharged matter, having zero angular momentum does not obtain a Schwarzschild solution before hell freezes over using general relativity without quantum mechanical considerations. It would seem the general solution would be the same.

 

Quantum Mechanics: Any hypothetical quantum solution would require violation of local causality--information would have to be transmitted at greater than the speed of light. Such a solution would admit 'time travel'; there would exist an inertial frame where matter would be in both the interior and the exterior at the same time. Sounds like Star Trek to me. No one has addressed this issue nor presented reference articles in argument.

 

Psychology: The desire for belief in these objects has attracted a following of religious quality. This social phenomena is currently played-out on the science channel, where the announcer declares their existence to be indisputable fact.

Edited January 17, 2014 by decraig

[Spyman]

The purpose of this thread was to find experimental and theoretical support for black holes.

 

There are other threads about black holes where existence is not questioned.

 

Physical Evidence: So far, I have found no supporting arguments or references to arguments of support.

Ohh - really? You don't seem to be very eager to find any such evidence or even be objective enough to listen to arguments in favor of black holes. IMHO your personal dislike for "black hole lovers" is a major obstacle IF your quest truly is to learn and understand.

 

[EDIT] Double post removed.

Edited January 17, 2014 by Spyman

[MigL]

Well decraig, we can agree that neutron degeneracy prevents the further collapse of spent stars up to a certain size limit.

As you don't believe black holes are a physical possibility, tell us your mechanism for for preventing the collapse of spent stars of mass higher than said limit.

 

And since you brought up Star Trek, as Spock says, 'once you've eliminated all possibilities, you must consider the impossible'.

[decraig]

Well decraig, we can agree that neutron degeneracy prevents the further collapse of spent stars up to a certain size limit.

As you don't believe black holes are a physical possibility, tell us your mechanism for for preventing the collapse of spent stars of mass higher than said limit.

 

And since you brought up Star Trek, as Spock says, 'once you've eliminated all possibilities, you must consider the impossible'.

1) Gravity prevents further collapse without the need of pressures due to matter. I've addressed this way back and multiple times.

Ohh - really? You don't seem to be very eager to find any such evidence or even be objective enough to listen to arguments in favor of black holes. IMHO your personal dislike for "black hole lovers" is a major obstacle IF your quest truly is to learn and understand.

 

[EDIT] Double post removed.

I guess you're irritated because I haven't directly answered your posts. Understandable.

 

Completely wrong. My dislike of black holes reflects my dislike of pseudo science. Perhaps you might examine your own objectivity if you have the skills in physics, or the manner in which you defer to authority if you don't.

 

So what do you have as best evidence that I already haven't shot down? Post any website or article written in English.

 

----------------------------------------------------------------------------------------

 

If anyone really wants to contribute, they should link professionally written supporting articles, rather than hearsay, gossip, or pop-physics lacking substantial support.

 

A derivation of the distance to event horizon or the central singularity for the general solution would be nice.

 

If you really want to pursue possibly viable arguments arguments against my stance, you might find something on naked singularities, an argument on physically measurable differences between black holes and incipients, or something in string theory.

Edited January 18, 2014 by decraig

[davidivad]

an event horizon is not a singularity.

it is simply the point where objects must have a velocity greater than the speed of light to break orbit.

a black hole is no more than a mass with an escape velocity greater than the speed of light.

the schwartzchild radius is an imaginary line that signifies where this escape velocity starts.

i had made a similar mistake trying to cure the entropy problem in a recent post.

Edited January 18, 2014 by davidivad

[decraig]

an event horizon is not a singularity.

it is simply the point where objects must have a velocity greater than the speed of light to break oYTa

Correct. The event horizon is a multiplicity of coordinate singularites. Do you have anything substantial to contribute?

 

I have 30 years in topics of mathematical physics. You need to do better than picking nits.

[davidivad]

Correct. The event horizon is a multiplicity of coordinate singularites. Do you have anything substantial to contribute?

 

I have 30 years in topics of mathematical physics. You need to do better than picking nits.

sometimes it is best to go back to the basics.

don't get me wrong; i am not disputing your knowledge.

 

is the amount of mass required to create a singularity across the surface area of the schwartchild radius greater than the mass of the black hole in question? remember that planck is a small man.

i move this assertion;

 

whether or not a black hole can ever have a singularity, the world may never know. it would seem that einstein's equations suggest a frozen star with an escape velocity greater than that of the speed of light. i could be wrong...

 

suggested reading: Frozen Star by George Greenstein (i love the classics)

Edited January 18, 2014 by davidivad

[Endercreeper01]

The event horizon is the place where the escape velocity is the speed of light. The distance from the singularity at the event horizon is represented by the Schwarzschild radius, R_s. It is given by [latex]R_s = \frac{2GM}{c^2}[/latex].

Nothing is ever able to go past the event horizon, even relative to the object accelerating towards the black hole. This is because the black hole is accelerating relative to something accelerating towards a black hole. Because of the equivalence principle, the black hole will experience time dilation. The time dilation is the same as that relative to an outside observer, i.e [latex]t=\tau \sqrt{1-{\frac{R_s}{r}}}[/latex]. When Rs=r, time freezes for the black hole relative to the object accelerating, so an object cannot get past the event horizon.

Edited January 18, 2014 by Endercreeper01

[imatfaal]

You don't seem to be reading answers. The old chesnuts have been answered and yet you persist as if no one else is contributing to this thread. A few reminders

 

"The black hole at the center of the galaxy..." is an oft repeated phrase on the science channels.

1) The cited evidence for this is the motion of stars at the center of the galaxy.

This evidence is insufficient. An object of highly collapsed matter would have the same effect.

...

This first line of questions of first post is incorrect
http://ned.ipac.caltech.edu/level5/Kormendy/frames.html

...2) The Schwarzschild solution having an event horizon is non-physical. The solution stretches over transfinite time. I imagine the same is true of the Kerr solution and the rest. Correct?

Should there be a black hole at the center of our galaxy, it would be a primordial black hole, having gained or lost very little mass, and only through Hawking radiation.

This reasoning repeated many times - as has been pointed out on numerous occasions is confusing a mathematical artifact (that can be avoided by coordinate system change) with a physical singularity. (for many posts) You seem to be conflating the red-shifting of an infalling object such that an accelerated observer never sees it cross the event horizon - with the mathematical singularity at the event horizon which is merely an artifact of the (wrongly chosen) coordinate system

3) The astronomy Gugus of the science channels also like to talk about things crossing the event horizon. Nothing crosses the event horizon to a stationary observer outside a back hole with the exception of virtual particles. To an Earthly observer, things don't cross the event horizon. Any objections?

The Gugus (? Presume gurus) probably admit that the observations of an observer in an accelerated frame are not the be all and end all. Sure there is a cognitive problem in that in falling objects will not be observed crossing the EH from an accelerated frame - but in their own frame there is no problem, and when the BH is viewed as a totality there is also no problem. By the time your infalling object is at a radius that the earth-observer is not seeing it move, it is so red-shifted and thus so indistinct due to the long wavelength that it merely appears as part of the black hole (which appears slightly enlarged)

4) this is just repeating the above confusion with the EH, and outside observers

I proffered an incipient black hole as such an object.
http://arxiv.org/abs/gr-qc/0609024

This article does not address an alternative explanation to the high velocities around small volumes of space that most physicists claim provides indirect evidence of a blackhole. In fact at no point does it question blackhole existence - it looks at the infalling/collapse era from the position of an accelerated observer though a quantum mechanical perspective

5) your list of articles regarding the qm protocol of blackhole formation - my response in post 49 remains unanswered

 

 

Correct. The event horizon is a multiplicity of coordinate singularites. Do you have anything substantial to contribute?

 

I have 30 years in topics of mathematical physics. You need to do better than picking nits.

No the event horizon gives a mathematical singularity in the schwartchild coordinate system - so simple don't use that system it clear breaks down (because of the mathematical singularity...) at the EH. Use Eddington-Finkelstein - or one of the other coordinate systems that do not break down

 

 

[decraig]

You don't seem to be reading answers. The old chesnuts have been answered and yet you persist as if no one else is contributing to this thread. A few reminders

 

This first line of questions of first post is incorrect

http://ned.ipac.caltech.edu/level5/Kormendy/frames.html

 

This reasoning repeated many times - as has been pointed out on numerous occasions is confusing a mathematical artifact (that can be avoided by coordinate system change) with a physical singularity. (for many posts) You seem to be conflating the red-shifting of an infalling object such that an accelerated observer never sees it cross the event horizon - with the mathematical singularity at the event horizon which is merely an artifact of the (wrongly chosen) coordinate system

 

 

The Gugus (? Presume gurus) probably admit that the observations of an observer in an accelerated frame are not the be all and end all. Sure there is a cognitive problem in that in falling objects will not be observed crossing the EH from an accelerated frame - but in their own frame there is no problem, and when the BH is viewed as a totality there is also no problem. By the time your infalling object is at a radius that the earth-observer is not seeing it move, it is so red-shifted and thus so indistinct due to the long wavelength that it merely appears as part of the black hole (which appears slightly enlarged)

 

4) this is just repeating the above confusion with the EH, and outside observers

 

This article does not address an alternative explanation to the high velocities around small volumes of space that most physicists claim provides indirect evidence of a blackhole. In fact at no point does it question blackhole existence - it looks at the infalling/collapse era from the position of an accelerated observer though a quantum mechanical perspective

 

5) your list of articles regarding the qm protocol of blackhole formation - my response in post 49 remains unanswered

 

 

No the event horizon gives a mathematical singularity in the schwartchild coordinate system - so simple don't use that system it clear breaks down (because of the mathematical singularity...) at the EH. Use Eddington-Finkelstein - or one of the other coordinate systems that do not break down

 

 

Do you expect a different result by changing coordinate systems?

[ajb]

The event horizon is the place where the escape velocity is the speed of light. The distance from the singularity at the event horizon is represented by the Schwarzschild radius, R_s. It is given by [latex]R_s = \frac{2GM}{c^2}[/latex].

Nothing is ever able to go past the event horizon, even relative to the object accelerating towards the black hole. This is because the black hole is accelerating relative to something accelerating towards a black hole. Because of the equivalence principle, the black hole will experience time dilation. The time dilation is the same as that relative to an outside observer, i.e [latex]t=\tau \sqrt{1-{\frac{R_s}{r}}}[/latex]. When Rs=r, time freezes for the black hole relative to the object accelerating, so an object cannot get past the event horizon.

This is not the right interpretation here. The problem stems from trying to use the coordinate time as the proper time as measured by some observer. The Schwarzschild coordinate time asymptotically corresponds to the proper time of a distant observer. It is not the proper time as measured by some infalling particle. Moreover, this also applies to the matter forming a black hole. On the surface of a collapsing shell you would measure a finite amount of time taken for the black hole to form.

 

This I think has been discussed here earlier.

[imatfaal]

Do you expect a different result by changing coordinate systems?

 

Of course - its a mathematical artifact (for about the twentieth time)

 

Eddington introduced the coordinates and LeMaitre proved that these showed that the mathematical singularity was strictly non-physical

 

You may wish to re-read Misner Thorne and Wheeler - Gravitation

§31.2. THE NONSINGULARITY OF THE GRAVITATIONAL RADIUS

 

and the following few chapters

[decraig]

what happens in one coordinate system happens in another up to the point where the coordinate map is poorly defined. What do you think happens in one coordinate system and not another?

 

What about 31.2?

 

Why don't you put some meat on the plate, imatfaal, instead of quoting chapter headings.

 

How does the proper time of an infalling observer compare to our Earthly clocks using your favorite nonsingular coordinates?

Edited January 19, 2014 by decraig

[decraig]

imatfaal, on 18 Jan 2014 - 07:52 AM, said:

This first line of questions of first post is incorrect

http://ned.ipac.calt...ndy/frames.html

I give up. Where in this article is there a counterclaim distinguishing galactic-center black holes from highly condensed matter?

 

Have you even read the article??

Edited January 19, 2014 by decraig

[davidivad]

decraig;

 

can you describe what you think the coordinate singularities are doing to affect the schwartzchild radius directly?

 

if you could explain your concept of singularity for me?

this might help me understand.

[Endercreeper01]

This is not the right interpretation here. The problem stems from trying to use the coordinate time as the proper time as measured by some observer. The Schwarzschild coordinate time asymptotically corresponds to the proper time of a distant observer. It is not the proper time as measured by some infalling particle. Moreover, this also applies to the matter forming a black hole. On the surface of a collapsing shell you would measure a finite amount of time taken for the black hole to form.

 

This I think has been discussed here earlier.

I mixed up [latex]t[/latex] and [latex]\tau[/latex]. They should have been switched.

But, it would still apply. The black hole would still be accelerating relative to the infalling object.

[decraig]

decraig;

 

can you describe what you think the coordinate singularities are doing to affect the schwartzchild radius directly?

 

if you could explain your concept of singularity for me?

this might help me understand.

The coordinate singularities do not effect the horizon radius. Based upon this question I don't think I could help with your second question without some knowledge of differential geometry.

 

------------------------------------------------------------------------------------------------------------------

 

 

imatfall, You demand I response to your post #49:

 

I’ve been overwhelmed by garbage, and so have tried to ignore irrational arguments demanding attention—but you asked for it.

 

You: Could you be more specific concerning where you believe those articles aid your argument? Most of this thread has been objecting to the concept of black holes through a classical argument (which I believe was flawed but nonetheless) with a few mentions of the information paradox. However, these articles - not exactly representative of the subject, basically by two researchers and various colleagues - are firstly not dismissive of the general notion of black holes as you seem to be, secondly are all trying to breach the as yet impassable division between the semi-classical approximations of black hole formation and a full quantum gravity explanation, and thirdly do not address the existence of black holes but rather probe the possibilities of their formation and the fact that we cannot at present provide a route of unitary transformation from infalling matter to a blackhole.

Your style of argument best belongs in the arena of debate rather than honest scientific inquiry. You did attempt to dismiss these articles, not on merit, but because there are few advancing the ideas contained. This is offensive. Here, you use words word such as “nonrepresentatibe,” only to obfuscate. This too is offensive. Can we please stick to science? This is where we attempt to justify claims rather than demanding disproof and raising straw men.

 

You: The GR basis of black holes Penrose/Hawking calculations has been shown above in the articles referenced by AJB - and there are regions of the universe within which there is such amount of mass within such a volume that we believe a blackhole per accepted these ideas is the only plausible explanation. We cannot go there to check - and frankly 'seeing is believing' went out of vogue in physics a few centuries ago - and other than that, the central volumes of spiral galaxies have all the predicted characteristics of black holes and continue to pass every test.

 

Again, “We believe” is not an argument. I’m too well healed to fall for your logical fallacies. This too is offensive. This one falls under “appeal to authority and the attempt to ostracize” You get two fallacy points for this one. More, you are incorrect to presume a black hole is the only plausible explanation without addressing physically measurable or theoretic difference of incipiants.

 

You: The fact that we cannot provide a method of formation that obeys the unitary rules of quantum mechanics would be intensely worrying if we had a functioning theory of quantum gravity - but we don't! The simplicity yet extreme conditions dictated by GR in the vicinity of a black hole may well be the clues required to get that theory - but you cannot use the absence of a pathway in an incomplete theory to throw away the mathematical formalism within GR and the observational evidence of black holes

 

Nonsense. I am not throwing away the mathematical formalism of general relativity nor ignoring observational evidence. A false accusation. This too is offensive.

 

And, no. I can, and do use the absence of a pathway to formation to argue that formation does not occur. Again with false accusation the logical fallacy. Again you give me offence. Please stop.

 

This has gone way off course. In future, I will not respond to your sort of rhetorical misdirection, but to science, reason, evidence and the honest persuit of knowledge.

Edited January 19, 2014 by decraig

[davidivad]

The coordinate singularities do not effect the horizon radius. Based upon this question I don't think I could help with your second question without some knowledge of differential geometry.

 

my appologies.

from your postings, i got the strangest impression.

i think that keeping a level head is important for getting to know the players in your field.

 

in my simplistic phrasing, you have not shown how you reach your conclusion in a complete manner.

please, humor me with some math.

[ajb]

But, it would still apply. The black hole would still be accelerating relative to the infalling object.

Is this an argument saying that nothing can fall in to a black hole or that nothing can escape a black hole?