Drunk on Black Holes

[Strange]

Notice that the Schwarzschild metric is invariant with time (it doesn't change over time).

 

This metric solution is insufficient evidence of physical black holes formatationbecause to make one, the metric has to change with time.

That is because it is an approximation to the real world using simplifying assumptions (as are all solutions to the EFE). More realistic situations (e.g. a black hole absorbing mass, or two black holes merging) can be modelled using numerical methods.

[Spyman]

 

I shouldn't really have to provide a reference on scientific consensus in the matter of black holes /snip/

I agree. You should not provide a consensus--provide evidence or scholarly papers instead. /snip/

 

Oh no, you do not get to just brush this under the carpet and then request for new references. I did provide evidence on scientific consensus in the matter of black holes and at this point I think you really need to clarify your position about it much much better.

 

Do you or do you not agree that the standard black hole model is a well established part of mainstream physics and that current scientific consensus holds black holes to be consistent with the theory of general relativity and current observations?

 

And IF you don't agree that the current status of scientific consensus is as I have represented it, then you need to explain what's wrong with my references and provide evidence of the negative nature of scientific consensus regarding the standard black hole model and any falsifying observations that have been made.

[decraig]

Oh no, you do not get to just brush this under the carpet and then request for new references. I did provide evidence on scientific consensus in the matter of black holes and at this point I think you really need to clarify your position about it much much better.

 

Do you or do you not agree that the standard black hole model is a well established part of mainstream physics and that current scientific consensus holds black holes to be consistent with the theory of general relativity and current observations?

 

And IF you don't agree that the current status of scientific consensus is as I have represented it, then you need to explain what's wrong with my references and provide evidence of the negative nature of scientific consensus regarding the standard black hole model and any falsifying observations that have been made

 

I already explained what's wrong with your referencing. You're doing the same thing as the other guy.

 

You're referenced an article. You did not cite any of its content. Did you get beyond the title?

 

Should you have bothered to read it, you would know that the article addresses experimental evidence that would distinguish between dark clusters and black holes, but not highly condensed matter and black holes.

 

Strange has something better to offer.

 

That is because it is an approximation to the real world using simplifying assumptions (as are all solutions to the EFE). More realistic situations (e.g. a black hole absorbing mass, or two black holes merging) can be modelled using numerical methods.

 

Of course; there is a distinction. Consider you already have a spherical black hole of mass M, and we throw a small mass, m at it. Does m cross the event horizon?

 

The mass, m perturbs our spherical black hole solution; the exact solution is not spherically symmetric.

 

So we use some numerical method. By experience we know it's not exact either, and subject to modeling approximation and floating point round-off. But the error introduced may itself be analytical or subject to numerical analysis.

 

I write a program to solve the n-body problem of multiple masses under mutual gravitational attraction. Each mass follows some curved path that I approximate with very small straight line section. To test the model I use a large central mass, and a small mass in circular orbit. Over time the orbital radius increased. I erroneously conclude that gravitational energy is not constant over time. dE/dt is greater than or equal to zero. This is a lot different than dE/dt=0. Making the straight line segments smaller does not change to result. Replacing the straight lines with polynomial approximational results in dE/dt=~0.

 

For black holes, the region of interest is near Rs. The functions of interest are gtt( r ) = 1/(1- r/Rs) and grr( r ) =1- r/Rs where r is very close in magnitude to Rs. r-Rs=epsilon, epsilon-->0.

 

Our numerical error will never be less than epsilon but we might try a change of coordinates, u=u(gtt,grr) and v=v(gtt,grr). We can then try doing the numerology in u and v than translate the results back to gtt and grr and hope that calculating gtt doesn't give us an NAN or stack overflow.

Edited January 24, 2014 by decraig

[Endercreeper01]

 

Notice that the Schwarzschild metric is invariant with time (it doesn't change over time).

 

This metric solution is insufficient evidence of physical black holes formatationbecause to make one, the metric has to change with time. It looks good on paper and the drawings are attractive, but the map is not the territory.

 

Do you see that you have to have a means of formation before you can justify models of existent black holes, or alternatively supply experimental evidence?

 

I've already addressed this.

The Schwarzschild metric can vary with time if there is motion, i.e if you have a function r(t). There is certainly motion when the core of a supernova compresses into a singularity.

Edited January 24, 2014 by Endercreeper01

[Strange]

This might be relevant (although it is hard to know what the thread is about)

Stephen Hawking: “The Absence of Event Horizons Means There are No Black Holes"

Edited January 24, 2014 by Strange

[MigL]

The asymmetrical collapse of various interacting masses to form a symmetrical black hole was addressed in the 60s by people like Wheeler , Thorne and Zel'dovich ( who called them 'frozen stars' as Wheeler's term , black hole, has vulgar connotations in Russian ). And no I can't quote references, do a search If you're interested. But you won't, your mind is made up, no sense peeking around the blinders!

 

Is your intent to re-do the past 50 yrs of high energy gravitational physics and cosmology ( as these theories apply to the very early universe as well )?

 

If so, you should give it a rest as I really don't think you're at the same level as the three named gentlemen, plus Oppenheimer, Novikov, Penrose and Hawking. You may well have been drunk when you started this thread.

Edited January 24, 2014 by MigL

[decraig]

The Schwarzschild metric can vary with time if there is motion, i.e if you have a function r(t). There is certainly motion when the core of a supernova compresses into a singularity.

 

If the metric changes with time, it is not the Schwarzschild metric. It would be a different metric.

 

This is the Schwarzschild metric:

 

 

Notice there are no terms containing 't' in the metric coefficients. A metric coefficient is the stuff in each term standing in front of ct^2, dr^2, dtheta^2 and dphi^2.

 

 

The asymmetrical collapse of various interacting masses to form a symmetrical black hole was addressed in the 60s by people like Wheeler , Thorne and Zel'dovich ( who called them 'frozen stars' as Wheeler's term , black hole, has vulgar connotations in Russian ). And no I can't quote references, do a search If you're interested. But you won't, your mind is made up, no sense peeking around the blinders!

 

Is your intent to re-do the past 50 yrs of high energy gravitational physics and cosmology ( as these theories apply to the very early universe as well )?

 

If so, you should give it a rest as I really don't think you're at the same level as the three named gentlemen, plus Oppenheimer, Novikov, Penrose and Hawking. You may well have been drunk when you started this thread.

 

You seem to have misunderstood. However, it is true that asymmetrical, irrotational matter will approach spherical symmetry under mutual gravitational attraction. This is due to gravitational time dilation where ingoing velocities of particles slow according to an external observer as they approach the Schwarzschild radius.

 

This was demonstrated by Rodger Penrose.

 

Penrose, Gravitational Collapse and Space-Time Singularities

Physical Review Letters Vol. 14-3 1965

 

Penrose examines the dynamics of matter external to the Schwarzschild radius. He does not examine the dynamics of formation. Your words, “to form a symmetrical black hole,” seem to be something extra you added in expectation.

 

Penrose continues with the post formation dynamics, ignoring the critical formation dynamics.

 

No one in 1965 had a formation solution. They skipped it. They made a lot of progress explaining what things look like afterwards, but couldn’t find a way to get there. By all evidence this state of affairs persists today. Not properly understood, it is a source of militant denial. It ranges from accusations that I am wearing blinkers, accusing me of not conducting research--and by others, deliberate fraud.

Edited January 26, 2014 by decraig

[Endercreeper01]

 

If the metric changes with time, it is not the Schwarzschild metric. It would be a different metric.

 

This is the Schwarzschild metric:

 

 

Notice there are no terms containing 't' in the metric coefficients. A metric coefficient is the stuff in each term standing in front of ct^2, dr^2, dtheta^2 and dphi^2.

 

 

 

Yes, but if the radius is changing with time (which is what happens in gravitation), the metric would also change with time.

[decraig]

Yes, but if the radius is changing with time (which is what happens in gravitation), the metric would also change with time.

 

I believe you refer to the radial coordinate.

 

But now I don't know what kind of solution to the field equations you might be talking about. Assuming spherical symmetry you want something like this:

 

[math]c^2d \tau ^2 = f(r,t)c^2dt^2 - g(r,t)dx^2 - d \Omega ^2 [/math]

 

What does that look like? It seems to violate Birkhoff's theorem...

 

http://en.wikipedia.org/wiki/Birkhoff's_theorem_(relativity)

Edited January 26, 2014 by decraig

[Endercreeper01]

Why does the metric require that it changes with time in order to be able to make a black hole?

[Spyman]

I already explained what's wrong with your referencing. You're doing the same thing as the other guy.

No, you have not and once again you evaded my question. You're doing the same thing as cranks.

 

Do you or do you not agree that the standard black hole model is a well established part of mainstream physics and that current scientific consensus holds black holes to be consistent with the theory of general relativity and current observations?

 

There is an important difference between acknowledging what the status of scientific consensus says and questioning its correctness, crackpots and science deniers often wants to blur and muddle this distinction because it gains them false credibility and casts doubts on opponents.

 

I am starting to suspect that you on purpose misinterpret my points and avoid to answer my raised arguments of the above.

 

There is nothing wrong with my references in regard to the content of my arguments!

 

Now, I have asked you to clarify your position more than once, why are you so unwilling to comply to this simple request?

[decraig]

No, you have not and once again you evaded my question. You're doing the same thing as cranks.

 

Do you or do you not agree that the standard black hole model is a well established part of mainstream physics and that current scientific consensus holds black holes to be consistent with the theory of general relativity and current observations?

 

There is an important difference between acknowledging what the status of scientific consensus says and questioning its correctness, crackpots and science deniers often wants to blur and muddle this distinction because it gains them false credibility and casts doubts on opponents.

 

I am starting to suspect that you on purpose misinterpret my points and avoid to answer my raised arguments of the above.

 

There is nothing wrong with my references in regard to the content of my arguments!

 

Now, I have asked you to clarify your position more than once, why are you so unwilling to comply to this simple request?

 

You certainly do have a lot of questions. Can you explain your obsession with taking votes?

Edited January 27, 2014 by decraig

[Endercreeper01]

 

You certainly do have a lot of questions. Can you explain your obsession with taking votes?

Do you, or do you not? Spyman's question was very clear.

 

Do you or do you not agree that the standard black hole model is a well established part of mainstream physics and that current scientific consensus holds black holes to be consistent with the theory of general relativity and current observations?

 

[hypervalent_iodine]

!

Moderator Note

Alright, enough. decraig, you have repeatedly ignored warnings about evading questions and ignoring the information that people are giving you. I am closing this thread for the time being for further staff review. Do not attempt to reopen the topic elsewhere.