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Three Air Tight Reasons Why No Object Can Ever Reach An Event Horizon


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Awal is just parroting stuff he was told. He thinks black holes are soft pillowy fluffy clouds to land on because Penrose and Thorne told him so. He thinks because if you're far enough from the singularity, none of the collapsed matter directly beneath your feet has any gravitational effect. He probably doesn't realize  Cavendish was able to measure the gravity of a mountain separate from the earth's gravity so AWAl is left to believe all gravity is relative to the center rather than what is right under his feet or beside him.

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I browsed the physics stack exchange for more about this, and I get conflicting answers from presumed experts. As you say black holes have life spans and not last for an infinite amount of time — they

You forgot to include the audio demonstration to identify the source of your research, i.e., the great Coasters, eh, Popeye?  Here ya go:  

Apparently, my understanding of BH physics is not as advanced as some of the other people posting here.   Therefore, unlike they, who are able to make grandiose proclamations drawn from their vastly s

Ever occur to you that you should pay more attention to respected physicists than to pseudo-scientific metaphysicians practicizing their craft on an internet message board, Awol?  Especially before announcing to the world what the undisputed scientific proof is?  I'd think about it if I were you.  But I aint you.

Actual physicists are the ones that say no object can ever reach an event horizon from an external frame. I can't believe how many times I've had to repeat this or that you're still trying to claim this isn't common knowledge and a universally accepted fact of how black holes work.

 

If anyone is in any doubt a very quick search will show you that no amount of time on any distant watch is enough for objects to reach an event horizon in the frames of those distant watches.

 

Without diving into this never ending and pointless argument that I find tedious, I would say that entering into the intense gravitational influence of a black hole would logically be disruptive to human life (and probably matter as we know it).    :blahblahblah:

No, you could definitely cross the event horizon (if that were possible) of a large enough black hole (super-massive-BHs) and be perfectly fine. It's only black holes below a certain mass that have strong enough tidal force to rip you apart before you reach the horizon.

 

Awal is just parroting stuff he was told. He thinks black holes are soft pillowy fluffy clouds to land on because Penrose and Thorne told him so. He thinks because if you're far enough from the singularity, none of the collapsed matter directly beneath your feet has any gravitational effect. He probably doesn't realize  Cavendish was able to measure the gravity of a mountain separate from the earth's gravity so AWAl is left to believe all gravity is relative to the center rather than what is right under his feet or beside him.

All I'm basing this on is standard black hole physics, not the views of any specific physicists.

Edited by A-wal
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If anyone is in any doubt a very quick search will show you that no amount of time on any distant watch is enough for objects to reach an event horizon in the frames of those distant watches.

 

All I'm basing this on is standard black hole physics, not the views of any specific physicists.

  

It's understandable that you don't claim to be presenting the views of any "specific physicists," because I doubt that any exist.

 

What you are trying to prove does NOT come from "standard black hole physics."  It is a product of your own misunderstanding and defective interpretation of physics in general, including a misunderstanding of SR.

 

Actual physicists are the ones that say no object can ever reach an event horizon from an external frame. I can't believe how many times I've had to repeat this or that you're still trying to claim this isn't common knowledge and a universally accepted fact of how black holes work.

 

 

Which is it? You just said you don't attribute it to any "specific physicists."  You can't seem to get through a single post without somehow contradicting yourself.

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No physicist has said this. What physicists say about what signals a distant observer see's and what is really happening are two different things.

No this isn't true. What a distant observer sees in this case is dependent on length contraction and time dilation.

 

The reason there's a slowing down of the photons from the falling object to the distant observer is because the falling object is length contracted and time dilated in the frame of the distant observer. It makes no sense at all to say that the falling object's photons are length contracted and time dilated but the falling object isn't.

 

The reason distant observers can never see falling objects reaching the event horizon is because length contraction and time dilation approach infinity at the event horizon in all distant frames. It is always possible for a falling object to accelerate away from the black hole, there is never a time that passes on any distant watch when the observer has reached the event horizon.

 

If any physicist has told you that there is a time on a distant watch when a falling object reaches the event horizon in the frame of that distant watch then they're certainly not representing the standard accepted view.

 

It's understandable that you don't claim to be presenting the views of any "specific physicists," because I doubt that any exist.

 

What you are trying to prove does NOT come from "standard black hole physics."  It is a product of your own misunderstanding and defective interpretation of physics in general, including a misunderstanding of SR.

It does come from standard black hole physics and is such a well established property of black holes that it can easily be found with a very quick search.

 

Which is it? You just said you don't attribute it to any "specific physicists."  You can't seem to get through a single post without somehow contradicting yourself.

Not any specific physicists, as in universally accepted or at least by the vast majority.

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.If any physicist has told you that there is a time on a distant watch when a falling object reaches the event horizon in the frame of that distant watch then they're certainly not representing the standard accepted view.

 

If any physicist has told you that the time on a distant watch controls the behavior of the distant object, then "they're certainly not representing the standard accepted view."  You came up with that monstrosity all on your own.

 

I'll concede, however, that the solipsism espoused by SR in general might well mislead an unsophisticated person to think this.  To hear SR disciples tell it, every frame of reference provides information which is "true," no matter how much two or more different frames may contradict each other about the "facts."

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Not any specific physicists, as in universally accepted or at least by the vast majority.

 

Well, if it's "universally accepted" then ALL physicists would agree, eh? If that's the case, then one would be around every corner. Yet you can't come up with even one "specific physicist"  who ratifies your claims. This is notwithstanding your assertion that "It does come from standard black hole physics and is such a well established property of black holes that it can easily be found with a very quick search."

 

What's up with that?

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There's a retarded boy who lives across the street from me.  All I have to do to convince him that what I'm telling him (that he should give me his lunch money, for example) is right is to preface my statement with the phrase "As everybody knows,..."

 

Works every time!  With him, anyway.

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If any physicist has told you that the time on a distant watch controls the behavior of the distant object, then "they're certainly not representing the standard accepted view."  You came up with that monstrosity all on your own.

 

FYI, Awol, the "quick search" you appeal to would, if you had ever done it, have quickly revealed that, contrary to your claim,  the object would enter the black hole, irrespective of what a distant observer might see: You might have saved yourself from ongoing embarrassment if you had done the slightest bit of research before presenting your "air tight" argument and then defending it to the death, ya know?

 

any object approaching the horizon from the observer's side appears to slow down and never quite pass through the horizon,[1] with its image becoming more and more redshifted as time elapses. This means that the wavelength of the light emitted from the object is getting longer as the object moves away from the observer.[2] The travelling object, however, experiences no strange effects and does, in fact, pass through the horizon in a finite amount of proper time.

 

 

https://en.wikipedia.org/wiki/Event_horizon

 

Personally, I'm not the least bit convinced that the first part of that quote is true, but that's not the issue here.

 

As I've said before, what you have done, contrary to the prohibitions of SR, is select one frame and treat it as an absolute, preferred frame.  But In SR the time in every frame is posited to be different.  You ignore this, and presume that the time in one frame controls the time in another.

 

As I already said:

 

What you are trying to prove does NOT come from "standard black hole physics."  It is a product of your own misunderstanding and defective interpretation of physics in general, including a misunderstanding of SR.
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If any physicist has told you that the time on a distant watch controls the behavior of the distant object, then "they're certainly not representing the standard accepted view."  You came up with that monstrosity all on your own.

As I've told you time and time again, the time on the distant watch is in no way controlling what happens to the falling observer.

 

It's just that if the falling observer doesn't ever reach the event horizon in the frame of a distant observer regardless of how long the black holes lives then all objects never reached the event horizon in any distant frame once the black hole has died and so are still there after the black has gone due to having never reached the event horizon in any distant frame, and we can therefore conclude that the falling objects can't possibly have reached the event horizon in their own frames of reference either.

 

Well, if it's "universally accepted" then ALL physicists would agree, eh? If that's the case, then one would be around every corner. Yet you can't come up with even one "specific physicist"  who ratifies your claims. This is notwithstanding your assertion that "It does come from standard black hole physics and is such a well established property of black holes that it can easily be found with a very quick search."

 

What's up with that?

It is a well established fact that objects can never reach an event horizon from any distant frame. You can deny it all you want but it's equivalent to denying that the Earth is generally regarded as round or that the universe is generally regarded as fairly big. True it's not quite as well known as those examples but it's every bit as silly to deny.

 

There's a retarded boy who lives across the street from me.  All I have to do to convince him that what I'm telling him (that he should give me his lunch money, for example) is right is to preface my statement with the phrase "As everybody knows,..."

 

Works every time!  With him, anyway.

What a lovely and insightful story.

 

FYI, Awol, the "quick search" you appeal to would, if you had ever done it, have quickly revealed that, contrary to your claim,  the object would enter the black hole, irrespective of what a distant observer might see: You might have saved yourself from ongoing embarrassment if you had done the slightest bit of research before presenting your "air tight" argument and then defending it to the death, ya know?

I'm well aware that according to the standard description of black holes objects can reach the event horizon from within their own frames. I have never claimed otherwise and this is the part that I'm refuting due to the fact that it directly contradicts the valid frames of distant observers in which falling objects are never able to reach an event horizon.

 

any object approaching the horizon from the observer's side appears to slow down and never quite pass through the horizon,[1] with its image becoming more and more redshifted as time elapses. This means that the wavelength of the light emitted from the object is getting longer as the object moves away from the observer.[2] The travelling object, however, experiences no strange effects and does, in fact, pass through the horizon in a finite amount of proper time.

 

https://en.wikipedia.org/wiki/Event_horizon

 

Personally, I'm not the least bit convinced that the first part of that quote is true, but that's not the issue here.

There you go, "any object approaching the horizon from the observer's side appears to slow down and never quite pass through the horizon". That's the only part I ever claimed was accepted physics. It doesn't matter how convinced you are, it's an unavoidable property of there being an event horizon to begin with.

 

It's not due to any type of illusion or falling objects having reached the event horizon in distant frames but observers in those frames being unable to tell. Take the case of an object closer to the event horizon accelerating away from the black hole. If that closer falling object hadn't reached the event horizon in the distant frame then no object farther away from the event horizon could have reached it either and we can take this example as arbitrarily close to the event horizon as we like.

 

The simple fact is that observers never reach the event horizon in any distant frame due to length contraction and time dilation approaching infinity at the event horizon. This is enough to show that objects are unable to reach the event horizon in their frames before the black has died due to the same length contraction and time dilation regardless of how long the black hole lasts.

 

As I've said before, what you have done, contrary to the prohibitions of SR, is select one frame and treat it as an absolute, preferred frame.  But In SR the time in every frame is posited to be different.  You ignore this, and presume that the time in one frame controls the time in another.

This in no way refutes anything in SR. It's only inertial frames that are never preferred over any other inertial frames, gravitationally accelerated frames are not inertial.

 

As I already said:

What you are trying to prove does NOT come from "standard black hole physics."  It is a product of your own misunderstanding and defective interpretation of physics in general, including a misunderstanding of SR.

I can see how it might came across that way to someone who has much trouble understanding this subject as you obviously do.

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Apparently, my understanding of BH physics is not as advanced as some of the other people posting here.

 

Therefore, unlike they, who are able to make grandiose proclamations drawn from their vastly superior knowledge, I am forced to examine this question from the viewpoint of humble mathematics (something that Moronium loaths and Awol unfortunately doesn’t understand)

 

A good place to begin, I think, is with the equation for gravitational potential energy:

 

[math]Gravitational\quad PE\quad =\quad \frac { GMm }{ { r }^{ 2 } }[/math]

 

To calculate the total energy in a line from the Swartzchild radius, [math]{ r }_{ s }[/math], to infinity, we just need to integrate that expression with respect to distance [math]{ r }[/math]:

 

[math]\int _{ \infty  }^{ r }{ GMm{ r }^{ -2 } } dr[/math]

 

Now, take the result and set it equal to the expression for kinetic energy:

 

[math]\frac { GMm }{ r } =\frac { 1 }{ 2 } m{ v }^{ 2 }[/math]

 

That will yield the kinetic energy of a particle drawn to the event horizon (EH) of a black hole (BH)

 

We know the Swartzschild radius, [math]{ r }_{ s }[/math], of the BH is defined by this expression:

 

[math]{ r }_{ s }=\frac { 2GM }{ { c }^{ 2 } }[/math]

 

So, we can use that fact to modify above equation to get:

 

[math]\frac { 2GMm }{ { c }^{ 2 }r } =\frac { m{ v }^{ 2 } }{ { c }^{ 2 } }[/math]

 

But that is just [math]\frac { { r }_{ s } }{ r } =\frac { { v }^{ 2 } }{ { c }^{ 2 } }[/math]

 

So, [math]{ v }^{ 2 }=\frac { { r }_{ s } }{ r } { c }^{ 2 }\quad and\quad v=\sqrt { \frac { { r }_{ s } }{ r }  } c[/math]

 

It is obvious when [math]{ r }_{ s }=r,\quad then\quad v=c[/math]

 

And that is what I needed to know! Objects infalling to the BH will reach the EH moving at the velocity of light and will certainly pass through the EH and enter the BH.

 

I suppose I could stop there as that answers the first question about whether or not objects can fall into a BH (the answer is YES) but there is another question about what the distant observer sees.

 

Photons that are near to any massive source of gravity, such as a BH, will be delayed in their path to a distant observer, and this is called the Shapiro time delay.

 

This is calculated by this expression:

 

[math]c'=c(1-\frac { 2GM }{ r{ c }^{ 2 } } )[/math]

 

Remembering that [math]{ r }_{ s }=\frac { 2GM }{ { c }^{ 2 } }[/math], the Shapiro time delay can be expressed very simply as just [math]v'=v(1-\frac { { r }_{ s } }{ r } )[/math]

 

Substituting for v, which was already calculated to be [math]v=\sqrt { \frac { { r }_{ s } }{ r }  } c[/math],

We have,[math] v=\left( \frac { { r }_{ s } }{ r } c \right) \left( 1-\frac { { r }_{ s } }{ r }  \right)[/math]

 

I am going to substitute x for [math]\frac { { r }_{ s } }{ r }[/math] and differentiate the expression wrt x:

 

[math]\frac { d }{ dx } (v)=\left( \frac { 1 }{ 2\sqrt { x }  } -\frac { x }{ 2\sqrt { x }  } -\frac { 1 }{ \sqrt { x }  }  \right) c[/math]

 

Damn! This is getting complicated plus I realize I am wasting my time but having gone this far I may as well finish it

So, setting the derivative equal to zero I should get the value of the ratio of [math]\frac { { r }_{ s } }{ r }[/math] that will yield the max/min values for v, as seen by the distant observer.

 

And that is just 3x = 1, so [math]\frac { { r }_{ s } }{ r } =\frac { 1 }{ 3 }[/math]

 

Substituting 1/3 back into the equation [math]v'=v(1-\frac { { r }_{ s } }{ r } )[/math] and solving for v’ gives v’ max/min as [math]\pm 0.385c[/math] we can safely disregard the minus answer and the 0.385c closely agrees with observation, as has been posted in this thread.

 

My conclusion is that the distant observer will see a maximum velocity of 0.385 c by observing an object in a region of space that is about 3 times the Swartzschild radius distant from the EH, and from there the object rapidly accelerates to a velocity of c as it enters the BH and crosses the EH.

 

The distant observer can never see the object at velocity c crossing the EH due to cosmic censoring (nobody can see this).

 

I suppose people can, and no doubt will, continue to speculate and argue endlessly about this but they can’t argue with the math (unless I totally botched it, which is entirely possible) Plus, the formula I used for the Shapiro delay is probably not exact enough to provide an accurate answer when the photons are emitted from an object that is closer to the EH than a distance 3 times the Swartzschild radius. So, there is still room for wild speculation and unsubstantiated claims to be made!

 

 

 

 

 

 

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It's just that if the falling observer doesn't ever reach the event horizon in the frame of a distant observer regardless of how long the black holes lives then all objects never reached the event horizon in any distant frame once the black hole has died and so are still there after the black has gone due to having never reached the event horizon in any distant frame, and we can therefore conclude that the falling objects can't possibly have reached the event horizon in their own frames of reference either.

 

 

 

Awol, you just won't quit, will you?  This is the third thread in which your absurd claims have been completely refuted, on any number of grounds, but you just keep on coming with the same unsupported (and unsupportable) claims.  One of those threads was even closed and moved to the "silly claims" forum.

 

You keep insisting that you are not claiming that one observational frame has an actual physical effect on another.  But then you just turn around and keep contradicting that assertion.  

 

I mean, just look at this:  "due to having never reached the event horizon in any distant frame, and we can therefore conclude that the falling objects can't possibly have reached the event horizon in their own frames of reference either."

Edited by Moronium
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I said I wouldn't venture outside my thread anymore but this is so impressive on a forum that contains so much ignorant garbage. I wonder how this is going to affect Moronium's theory of garbage in, garbage out therefore everything must be garbage when it comes to math. This post makes me want to re-acquaint myself with university calculus which I've never had to use. It's like a ray of light on a hopelessly dismal landscape of sheer stupidity.

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To calculate the total energy in a line from the Swartzchild radius, [math]{ r }_{ s }[/math], to infinity, we just need to integrate that expression with respect to distance [math]{ r }[/math]:

 

And that is what I needed to know! Objects infalling to the BH will reach the EH moving at the velocity of light and will certainly pass through the EH and enter the BH.

 

 

 

I may not quite understand what you're saying here Popeye, but infinity is not involved here, is it? The object could be approaching from a distance much less than infinite. Nor is an object necessarily approaching a black hole in "free fall."

 

I've seen physicists claim that an object can enter a black hole at any speed between 0 and c.  The idea seems to be that accretion disks surrounding the black hole will show down the approaching object and put in a series of orbits which spiral toward the black hole.

Edited by Moronium
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...gravitationally accelerated frames are not inertial.

 

 

Yeah, so what?

 

To repeat a previous point, experiments show that gravitational time distortion affects clocks, not "time itself."  Gravitational clock retardation could be so severe as to completely stop a clock in a particular frame, but that would not stop "time" all over the universe.  The BH would just eat up a stopped clock along with everything else, that's all.

 

A stopped clock in one frame doesn't suspend gravity all over the universe, eh?  You just keep on mixing frames in illogical ways. Now you impute the approaching object's frame to the black hole itself.

Edited by Moronium
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 I wonder how this is going to affect Moronium's theory of garbage in, garbage out therefore everything must be garbage when it comes to math. landscape of sheer stupidity.

 

That's not my theory, Ralf, but I know you can always be counted on to make invalid inferences from a statement, then build up a strawman from the material that fallacious reasoning supplies.

Edited by Moronium
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To repeat a previous point, experiments show that gravitational time distortion affects clocks, not "time itself."  Gravitational clock retardation could be so severe as to completely stop a clock in a particular frame, but that would not stop "time" all over the universe.  The BH would just eat up a stopped clock along with everything else, that's all.

 

I find it somewhat disconcerting that I can't help Popeye, normally a reasonable guy, see this.  He just equates "time" with clock ticking rates.

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