Neutron Star

After my claim above, I decided to do some googling and checking to confirm.
It appears my certainty in that a BH has no upper mass limit is not so certain.
Still my claim was supported by the following.....
Paddoboy is correct about this as well. There is no limit. The mass is simply a parameter in Einstein's equations that can take any value. The black hole at the center of the galaxy has a mass of 2x10^6 solar masses. Quasars and other active galaxies show evidence for supermassive black holes that are a thousand times more massive (over a billion solar masses).

Best wishes,

Bennett Link
Department of Physics
Montana State University
Which all made perfectly good sense to me.
Until I found the following.......
http://arxiv.org/abs/0808.2813

Tashja, sincerely you have done a great job in confirming beyond any reasonable doubt that the current topic paper, the subject of this thread is invalid.
But the continued "questioning" of the Professor's replies, may have him growing somewhat tired and maybe getting dismissive of the answering of so many questions.
But just maybe, it would be most helpful if he could explain what he thinks of this above paper in light of what I thought [ and still do] re the question of the upper mass limit of BHs.


As an aside, Rajesh answered when Professor Link confirmed my claim about no upper limit replied.......

Then later in post 227 he posted the following which seemed to align with what was theorised in http://arxiv.org/abs/0808.2813

Perhaps he decided to google himself and came across the same paper?

Remembering that when we speak of any theoretical mass limit to BHs, [ according to my linked paper] we are speaking of 10 billion solar masses, termed UMBH [ULTRA MASSIVE BLACK HOLE]


Not that this really has anything to do with the invalidity of the paper this thread is originally about, but it is a point which has emerged.

Again tashja, without making a nuisance of yourself, if the good Professor could pass a comment it would be most helpful.
Of course it goes without saying that any comments by our online reputable posters like OnlyMe, origin or brucep would also be welcome.

 

Log in or Sign up to hide all adverts.

Well I'll just reply to myself since Rajesh can't seem to answer a question associated with a derivation for r_ouch and Tau_ouch. r_ouch is where the falling object will be when it begins to come apart and Tau_ouch tells us how long to r=0 from r_ouch. As predicted by local rain coordinates. IE GR. Where would delta g across the falling neutron star exceed the forces binding the neutronium. An amateur guess, by me, would be > the strong nuclear force. BTW my purpose for discussing the duel ouch is to point out that everything that falls across the Schwarzschild event horizon winds up at r=0 in the Schwarzschild geometry. That's the geometry all the Professors are assuming. Rightly of course. Guess what there are other solutions to the Einstein Field equations where everything doesn't have to wind up at r=0. This paper I'm going to link is about the possibility of stable orbits and life inside the black hole described by these solutions. One being the Kerr-Newman.
http://arxiv.org/abs/1203.0878
Anybody interested look at the citations. Some pretty esoteric physics. Actually that one was for rpenner. This is the one for the rest of us.
http://arxiv.org/abs/1103.6140

 

Log in or Sign up to hide all adverts.

The paper you linked is very interesting for me. I just looked up UMBH and the top limit noted could be as much as 40,000,000,000 solar mass. If this were the Schwarzschild geometry the average proper velocity, dr/dTau, would be 3/2 c over the path from r=2M to limit r=0. So this would mean that it would take ~ 1.51 days proper time, dTau, to reach r=0 after crossing r=2M. Building large theoretical black holes for theoretical study is a common theme in GR text. Never thought it could be that big in actuality.

 

Log in or Sign up to hide all adverts.

Interesting brucep......I would imagine though theoretically speaking, any BHs mass limitation would depend on how big the Universe is.

Please Register or Log in to view the hidden image!

And as according to present data, the Universe is most likely Infinite in extent, [ignoring the methodology/theoretical concept of the paper in question] therefor infinite in content, the theoretical mass limit would also be infinite.
The mind boggles!

Please Register or Log in to view the hidden image!

The aspect of time would also be a consideration.
An Interesting aside.

 

http://www.phys.vt.edu/~jhs/faq/blackholes.html#q2
How big can a black hole get?
There is no limit to how large a black hole can be. However, the largest blackholes we think are in existence are at the centers of many galaxies, and have masses equivalent to about a billion suns (i.e., a billion solar masses). Their radii would be a considerable fraction of the radius of our solar system.

 

dTau is the wristwatch proper time of the falling object. To get the average proper speed over the path is another simple derivation. 3/2 c is what it comes out to be according to GR. It's actually the first part of the link I provided for Rajesh.

 

Really pad , they exist , these BHs' ?

This is nonsense pad and you know it .

 

You'd probably fit the bill for 'denser than r=0. To bad they think trolling is acceptable behavior.

 

All you need to do river you old smarty you, is come up with some alternative proposition as to what causes the effects on time and space that we so often see.
Or as per usual, is this just another of your many exercises of pissing into the wind?

Please Register or Log in to view the hidden image!

 

And ladies and gentlemen, this attempt at derision of BHs come from our old friend river, who still believes in ghosts, giants, goblins, fairies and UFOs of Alien origin with anal probe technology!

Please Register or Log in to view the hidden image!

Everytime he posts, he gets a bigger laugh then Bozo the Clown!

 

Hmmm...really pad

pad believes in the absolutes of our current knowledge of particle physics , hence through infinity our knowledge and therefore our understanding of these stars will never change our current knowledge on these stars .....!!!!!

 

Obviously brucep, Rajesh's paper that is the subject of the thread, is well and truly defunct and totally impossible.
Perhaps this "aside" on the BHs maximum mass could be the subject of another thread?

 

Time changes ....thinking

 

UMBH. GR would predict no upper limit but they're so many components in Galaxy formation that the UMBH becomes a limit based on what is known to have happened rather than on what is theoretically possible. Pretty cool. I expect Rajesh to think the papers on stable orbits inside black holes to support his hypothesis. LOL. Cranks are really predictable.

 

So are mainstream thinking , predictable and hence the response

 

? Cut the cryptic bullshit.

 

Times change sure...and theories are modified. But yourself and your agenda are stuck in a rut.
Get over it and yourself, and please stop sidetracking this thread with your nonsense.

 

I'm with the theoretical no upper limit scenario still.

 

Paddoboy,

That UMBH paper is by some Yale astrophysicist and quite recent......but the actual upper limit is derived much earlier by a simple calculations based on Thermodynamics (entropy consideration) and it is around 10^8 Solar Mass. Please do some more googling, you will get it. I feel, Prof Bennett did not get into it, simply because he did not want to bring in Thermodynamics, moreover as I stated earlier, my question is not about accrued mass limit, it is about initial core mass which can become BH. Q-reeus understood the point, I am afraid you have not.

And as far as my paper getting defunct, I don't agree, it has 3 other conclusions

1. Neutron Star mass range 1.4 to 2.65 Soalr Mass
2. Quark / Exotic Matter Star Mass range 2.65 to 3.24 Solar Mass.
3. BH Minimum Mass = 3.24 Solar Mass

These 3 are substantial conclusions...now coming to another conclusion (BNS) that is NS like structure inside EH, the main problems are causality violation (Prof Hamilton), another problem is p = 0 not possible at surface inside EH (Prof Bennett)....so let me see and rework with maths how these two objections work out. But I am still intrigued....pl think about it carefully.....the causality violation comes at around 4/3Rs for smaller cores....so how BH can form from NS ?? How the core can compact to Rs when it has to pass through violation point much before that ? This is the question which I asked Prof Hamilton through you, for which you did not get any further response, and this is the question which Prof Bennett responded but I could not decipher the answer to my question from his response...

......I am still stuck...and I feel rightly so.......that a BH may not form from at least some NS mass accretion type scenario as something catastrophic must happen when core is about to approach 4/3Rs...........yes there is some reference to compressibility/impregnability of Neutrons/Neutronium, but then this limit 4/3Rs would have been derived scientifically keeping in view this aspect. This also cannot be the case that this collapse (from NS to BH) takes place very fast and in this hyper chaos the core gets inside its own EH and after that no way out.....that will make the entire BH formation from NS a poker game (chance scenario).

 

Must disagree with you again and your calculations, but I will reserve my full opinion as to no theoretical upper mass limit according to any professional replies...which is what we both need to do.
Yes, Initial core mass to BH is another matter.

There were no other conclusions that are not already theoretically known previously.
Otherwise, like I said, the claim of the paper, is an absurdity...To claim otherwise is to throw GR and BHs out the window...and therein lies your agenda.
You need to accept that.