Gravitational waves from black hole merger

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Fossil fields as the name suggests are simply the gravitational field of a large star before it goes S/N and leaves a BH remnant...that also pertains to EMF's and explain how gravity and such "gets out" of a BH.
I'm sure I also gave you a link confirming that.
http://math.ucr.edu/home/baez/physics/Relativity/BlackHoles/black_gravity.html
If a star collapses into a black hole, the gravitational field outside the black hole may be calculated entirely from the properties of the star and its external gravitational field before it becomes a black hole. Just as the light registering late stages in my fall takes longer and longer to get out to you at a large distance, the gravitational consequences of events late in the star's collapse take longer and longer to ripple out to the world at large. In this sense the black hole is a kind of "frozen star": the gravitational field is a fossil field. The same is true of the electromagnetic field that a black hole may possess.

 

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Err, no. In standard GR speak, a BH 'fossil field' can only refer to the gravitational remnants left behind *after* a progenitor star has undergone S/N & core collapse. That such field can be determined from the field of the progenitor star (subsequent quote) is a separate and rather obvious fact.

That last sentence is a catch-all that is technically incorrect, since it implies a BH may possess an intrinsic magnetic field, in addition to an electric one. A BH per se can according to consensus GR theorists theoretically possess an appreciable electric field, but not a magnetic moment. Many BH candidates are certainly associated with magnetic fields, but only as a consequence of an accretion disc (actual source of field), which nobody except maybe one or two fringe theorists would allow was present during the nominal BH-BH merger detected by aLIGO. And that merger event is THE basis of thread topic.

 

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I accept that correction, and admit I put that rather poorly....

I don't believe that is correct. There is just as much likleyhood, in fact more, of a large star with a EMF field becoming a BH, as there is with any associated with accretion disks.

 

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Of course there is agreement progenitor stars can and often do possess significant large-scale magnetic fields (but negligible net electrical ones). It is admittedly surprising that while a BH can possess spin thus angular momentum, that does not translate into possibility of a corresponding *intrinsic* magnetic moment. See e.g. first part here:
http://www.natureasia.com/en/nindia/article/10.1038/nindia.2015.156

Similar remark appears first part here: https://www.astro.umd.edu/~miller/teaching/astr498/lecture19.pdf
So accordingly what must happen is that any stellar magnetic moment is entirely shed into the surrounding expelled envelope during a S/N & core collapse event proceeding beyond NS - i.e. total core collapse.
Of course there are rival theories that do admit intrinsic magnetic moments; to say whatever collapsed entity resides at Sgr A*. One earlier study strongly suggests just that, but no general agreement exists. Hence current efforts at resolving physics close to assumed horizon there are awaited with great interest by various theorists.

 

But that was selectively copy pasted by Paddoboy from the link given, on the face of it, it appeared as if Paddoboy was explainng the contents of the link, but it is not so.....

 

No ! Thats no physics.

Can you please try to ponder over following, with mainstream perspective, you can add your objection as well..

1. What is the meaning of the mass of a BH ?
2. Where and in which form it resides ?
3. Where does the Gravitational Field of a BH resides and how it interacts with other objects outside EH ?
4. What about the initial angular momentum of a collapsing core ?
5. Where does rotational energy resides ?
6. Where does the charge or electric field of a BH resides ?
7. How the various energies of a BH can be taken out ?
8. Is there any possibility of mass to EM radiation conversion for a BH ?
9. What is the source of GW energy and how it happens ? (Seems to be your main prick)
9. What happens to an accreted mass's gravity, charge and spin ? How it increases/decreases Gravity, Spin, charge etc of a BH ?

Take all these points one by one, try to find out the mainstream consensus on these points and after that you can frame your objections...this will lead to meaningful learning.

 

My comments were made without having checked original source, but had actually assumed that quoted was by original author. Either way, the statement itself, likely just sloppy language rather than conceptual error, is what was being addressed, not anyone in particular.

 

I think any good site on BH will have all the answers to your above questions.

My main concern is how E of E=MC^2 becomes GW energy. Do you have any reference/link for that?

 

No one has suggested any general agreement exists on such properties as intrinsic EM charge, but a well accepted theory suggests that a charged spinning BH, and associated twisted magnetic field lines, is at least partly responsible for the polar jets we often see with BH's.

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Considering that little swipe you refer to emenates from a source that cannot even understand that any measured density of a BH is not really relevant or even make any sense is amusing to say the least.


Getting back on subject, I see the confirmation of BH's as being as Important an issue as the confirmation of gravitational waves...Not that there was too much doubt about either's existence prior to aLIGO.

 

???? Within GR there is complete agreement. Charge invariance holds during collapse, hence if any net charge is 'swallowed' by BH, it will show externally as intrinsic and undiminished Coulomb electric field. No-one expects any *appreciable* net BH charge stemming from realistic astrophysical processes.

Really? A 'well accepted theory'? If your claim of an intrinsic magnetic field, owing to spinning charged BH is true, it represents a fundamental schism within GR. Any links to reliable sources backing up your position? My own claim as it relates to GR's position is well known: https://en.wikipedia.org/wiki/No-hair_theorem

Seems you rejected those two references I gave in #324, which simply accord with no-hair theorem. And further rejected last para in #322 which dealt with the actual source of BH magnetic field allowed for in GR - accretion disks. Which are external to the BH proper hence as stated earlier, mean there is an associated not intrinsic magnetic field.
If one searches hard enough and long enough, there's bound to be uncovered some theorist out there claiming different, but you wish to be associated with 'fringe', non-mainstream mavericks?

 

I'll leave that to you.
And I'm sure if you do your own searches [which at this time I do not have enough time, as I'm off to a Harbour Cruise shortly, you'll find that the polar jets are thought to be a result of twisted magnetic field lines.
And yes, certainly, as I had trouble telling both rajesh and the divine one, any BH charge is relatively quickly negated.
Back later.

 

Which contradicts anything I wrote in #330 how exactly?

 

You missed the point, those questions are for you to know with respect to what mainstream says about them. In one of the posts you talked of BH mass as some kind of atomic structure, suggesting your lack of understanding of mainstream BH explanation. since assignment of mass, charge, energy, angular momentum, gravity etc with Black Hole is not according to conventional wisdom, and hence first you should know that, once you know that and get convinced then probably you will get your answer how energy/mass can be extracted from BH.......None knows where the BH mass resides, so there is no conventional conversion method like fission / fusion for BH GW......

 

Consider the Equation "E=MC^2". This equation accounts for mass loss in the interactions of atomic particles. This equation is also accounting for mass loss in the two BHs collision. In the case of interactions of atomic particles, the "E" represents EM energy. In the case of two BHs collision, the "E" represents GW energy. Why the "E" becomes different in these two cases, though the same equation is used in both the cases. Can you explain this mystery?

 

That's just more cop out inspired rubbish.
Let me reiterate for the umpteenth time: GR tells us that once the Schwarzchild radius is reached, that further collapse is compulsory....That means that the mass continues to undergo collapse until at least the quantum/Planck level is reached, which is then beyond the parameters of where GR is applicable: GR is a classical theory and after rcent confirmations we have absolutely no reasons to doubt its predictive powers.
In essence then its obvious the mass does reside at or below that quantum/Planck level and to which we refer to as the Singularity.

 

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As I said, any EMF is relatively quickly negated. A Kerr-Newman BH could generate a small magnetic field, which like charge and spin is negated over time: In other words the outcome of any and all BH's are the simple Schwarszchild solution, and than over the lifetime of the Universe final evaporation via Hawking Radiation as logically predicted and supported by quantum interactions.
And yes, we also have theories that if a Neutron star with a significant magnetic field, collapses to a BH, then part remains of the magnetic field can remain trapped near the EH.
And no I don't see them as anti mainstream, heaven forbid!

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Electromagnetic energy isn't converted into gravitational energy at any time. I've explained this for you to many times for me to think you want to understand the physics. You just want it to be the way you imagine it should be. Go away.

 

It's not E=MC^2. In geometric units it's E=M. In conventional units it's E=mc^2. C is not the symbol for the local speed of light. It's c. c^2 isn't speed or velocity. You shouldn't have any concerns before you understand the physics. You're just flapping your jaw. E=M is rest energy and rest mass. Both are invariants when expressed this way.

 

Totally true.....
Reminds me of 10 points I once started a thread on that all alternative hypothetical pushers need to adhere to: Grumpy, [remember ol Grumpy] agreed and added another final all encompassing point: Any potential alternative hypothesis pusher, need to understand the incumbent theory totally first.

 

There is no such known property as 'intrinsic EM charge'.......