Dark matter and black hole.

And here I was just going to withdraw my complaint. Fuck that.

 

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I've told you where you are wrong: Let's say just about everywhere.

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Like I said, I see you as the dishonest party, and that is evidenced by the past threads of yours that were shifted to the fringes.

 

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There is no functional difference between M/r and M/r^3. Thats what Physbang says.

This guy seems to know nothing about physics but he pokes his nose everywhere and pretends to know some physics. His posting should be filtered for two accounts. Gullible posters Like Paddoboy feels he is reputed, so his incorrect posts may be harmful to such posters. Secondly his frequency of use of f word has gone up.

 

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James R,

You have fallen prey to a very obvious mistake. This M/r was a straw taken by Physbang, when I showed him that for a BH, M/r need to have a certain value not M/r^3.

It will not be difficult for you to realize your mistake that for a sphere linear mass density M/r has no meaning. It is generally used in the context of a cylinder or rectangular rod etc where cross section along the length (M/l) is uniform. Pl note for sphere M/r is not at all meaningful and it is not functionally same as density.

This forum certainly needs an objective Mod who can curb mistakes or stupidity in science forum at the beginning. You let this man Physbang continue with his foolish argument, then he became abusive, I could not match his tone, so I reported and you shot the messenger. What kind of modding is this?

Both his argument about BH formation dependence on density and DM BH evaporating are meaningless. And look at his arrogance, look at his language.

 

And yet it is your subject matter and erroneous claims that end up in various sections of the fringes.
Let me again inform you, and rajish and our past friend expletive deleted, as brothers in arms, in the similarity of your views, none of you have yet invalidated any of what is accepted mainstream physics/cosmology.
You blabber on about GP-B being fraudulent, about aLIGO being fraudulent, you fail to understand, actually you just simply deny that when Schwarzchild radius is reached, further collapse is compulsory, you also fail to recognise that all forces are overcome by gravity as mass heads towards the core of the BH, you obfuscate about well used scientific terms such as Spaghettification and the core of a BH, either out of ignorance or just plain contrariasm, you actually along with your two brothers in arms, deny just about all 21st century cosmology, then, you act all indignant like when someone puts 2 and 2 together and sees the methodology in all this madness as simply and insideously a god of the gaps insertion and/or implication.

Or perhaps James may be waking up to what some of us already know.

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Let me say that your rather fabricated pacifist indignant style is a mirror image of that used by expletive deleted.
And once again, your silly claim re density and BH are plainly wrong, and any good physics book on the subject will tell you that.
Or if you like you could provide a link, citation or reference to support your claim.....a request I have made previously to no avail as yet.
here's a simple WIKI link for you....................
https://en.wikipedia.org/wiki/Black_hole
Objects whose gravitational fields are too strong for light to escape were first considered in the 18th century by John Michell and Pierre-Simon Laplace. The first modern solution of general relativity that would characterize a black hole was found by Karl Schwarzschild in 1916, although its interpretation as a region of space from which nothing can escape was first published by David Finkelstein in 1958. Black holes were long considered a mathematical curiosity; it was during the 1960s that theoretical work showed they were a generic prediction of general relativity. The discovery of neutron stars sparked interest in gravitationally collapsed compact objects as a possible astrophysical reality.

Black holes of stellar mass are expected to form when very massive stars collapse at the end of their life cycle. After a black hole has formed, it can continue to grow by absorbing mass from its surroundings. By absorbing other stars and merging with other black holes, supermassive black holes of millions of solar masses (M☉) may form. There is general consensus that supermassive black holes exist in the centers of most galaxies.
>>>>>>>>>>>>>>>>>>>>>>>>>>
Obviously inferring density.
But again, if you have any reference, link, or citation claiming otherwise, then please reveal it.

 

This is the third time I am asking you what is wrong?

You keep saying wrong wrong, but what is wrong?

 

rajish, I'm not playing your games: Your crusade here, has been obvious since you first started probing the forum, with simple astronomical questions to feel everyone out, before you emerged from the closet so to speak.
Your answer has been given more than once.
Check out the accepted mainstream definition of a BH, then you have your answer.
But please don't confuse how dense an object needs to be to become a BH, with how dense the BH is once it is formed [in reality, a nonsensical aspect, as you have also been told]

 

No, I am very clear on that, infact you guys are incorrectly associating density.

In general there is no relationship with certain density of an object to become a BH. For smaller massed object, the density will be higher and vice versa as the density just at EH is inversely proportional to mass squared.

It is not of any value to talk of density once inside EH.

 

No we are not.

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Please show a citation and/or link supporting your stance.

Wrong. For any object/mass to become a BH, it must be squeezed to a density where its Schwarzchild radius is reached.eg: Earth, to the size of a marble: The Sun to within around 6 kms diameter or 3 kms Schwarzchild radius.
The Schwarzschild radius of an object is proportional to the mass.
https://en.wikipedia.org/wiki/Schwarzschild_radius
Schwarzschild radius (sometimes historically referred to as the gravitational radius) is the radius of a sphere such that, if all the mass of an object were to be compressed within that sphere, the escape velocity from the surface of the sphere would equal the speed of light. An example of an object where the mass is within its Schwarzschild radius is a black hole. Once a stellar remnant collapses to or below this radius, light cannot escape and the object is no longer directly visible, thereby forming a black hole.[1] It is a characteristic radius associated with every quantity of mass. The Schwarzschild radius was named after the German astronomer Karl Schwarzschild, who calculated this exact solution for the theory of general relativity in 1916.

 

This is the problem text in general. Words like compress and squeeze create that kind of impression. And this is true for stellar objects but not in general. Like for a sun to be a BH, it needs to be squeezed thus higher density. but for our MW mass BH the density shall be very less. So it cannot be said that a certain density is required for BH formation.

 

So not only do you blow off James questions (and appologize to PhysBang), you double down and continue with the insults.

How Trump like of you.

 

I am very sure, you have basic understanding of linear mass density, and my post #46 is quite clear. You should ask Physbang to apologize for insisting with mistakes by stating that M/r is functionally same as density for a sphere. M/r has no significance for a sphere as this can never be constant if the density is same.

Take for example if I say a cylinder has a linear mass density of 100 kg per meter, then the mass of a 10 meter long cylinder is 100*10=1000kg. Now can you say that the linear mass density (M/r) of a sphere is 100 kg per meter, so the mass of a 10 meter radius sphere is 1000 kg? Can you?

Will you withdraw your trump comment?

 

You continue to ignore James request - I am so not surprised. I do not wish to hijack the thread further, so I am finished responding further.

Why? Doubling down on incorrect information is a hallmark of Trump. If it really bothers you I will withdraw that you are Trump like and say your responses and actions are 'The God' like. Happy now.

Good bye.

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I can understand your problem. You have no courage to side with the truth, you side with the people.

 

Because I don't really give a shit anymore, let me say quite clearly why RajeshTrivedi is a fucking moron: in a spherically symmetric solution, giving a radius describes a sphere, and thus volume.

Is "fucking moron" the correct term? Colloquially, yes, since I'm speaking here of my opinion, not his actual IQ (which I care not one whit about). No, I mean that RajeshTrivedi is a purveyor of fantasies about physics with little regard for the facts and only regard for attempting to make himself look intelligent. Thankfully, he just looks like a fucking moron.

 

Reported.

 

Sorry do not want to get in a flame war - it is a waste of time.

 

As I learned from reporting your piece of shit post calling me a liar, nothing is going to fucking happen. So enjoy this level of discourse.