Black hole?

[Mordred]

OK I can see I have a bit of work cut out for me here. OK lets start with the problem of "Where does the energy come from". Well energy is simply a property that is defined by the ability to perform work. So it doesn't need to come from anywhere, it doesn't need to be created but simply emerges for various applications.

Start with Potential energy: "In physics, potential energy is the energy possessed by an object because of its position relative to other objects"

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

So by merely changing the position of one object compared to another I change the potential energy....

Kinetic energy: "In physics, the kinetic energy of an object is the energy that it possesses due to its motion"

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

Now what about mass?

Mass "is both a property of a physical body and a measure of its resistance to acceleration (a change in its state of motion) when a net force is applied"

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

So looking at those statements Does energy need to exist in the first place or does it simply develop as field anisotropies develop via potential differences between two or more measurement points ? much like voltage in electrical circuits?

Now as for the universe temperature. There is a very important relation between the density of particles in a given volume. This is simply the ideal gas laws in play. Yes pv=NRT. If you take x number of particles and compress them, the temperature will increase. To do otherwise would violate the laws of thermodynamics...

In Cosmology applications the temperature follows a very interesting relation it is the inverse of the scale factor.

[math]a=\frac{1}{T}[/math] that is a direct application of those ideal gas laws I just mentioned above.

The question of the laws of physics becoming invalid in BH's depends on how one defines those laws of physics. In mathematical precision its when symmetry can no longer be applied. It would take a bit to fully describe that under math as it requires an understanding of various notations many aren't accustomed to but if you like I can readily post the mathematical descriptive.

 

[MigL]

" having read some of your posts on political issues, we will never agree " ????

Maybe that's your problem, Interested, you confuse political OPINION with scientific FACTS and OBSERVATIONS.

[Strange]

On 26/11/2017 at 8:56 PM, interested said:

With all your none consistent posts

"inconsistent"

[interested]

I see I am excelling myself -20 points for wondering about what is inside a black hole so far. If I was a child in an infant school I may be upset. But I guess it is fun to express your feelings.  I have also observed being annoying on the forum seems to get better answers and more -ve points. So I guess I should change my user name to annoying instead of interested.  

I think everyone who is interested will be aware if you look at the big bang theory at look at what is inside a black hole, there are definite correlations. In a black hole as matter and volume are compressed it is going to get hot. If enough matter is compressed inside a black hole the temperatures will match those prior to the plank time of the big bang  see https://sites.uni.edu/morgans/astro/course/Notes/section3/bigbang.html . Matter will become pure energy in the form of radiation due to temperature and pressure inside a blackhole that is big enough. How is this different to a big bang? The mass is consumed converted into energy, gravity collapses damn thing explodes releasing tonnes of energy like a big bang, if the black hole is spinning then the energy will be released in the form of a spiral galaxy.

Blackholes as I understand have not been observed colliding as yet, but in theory they could, as did recently with the neutron star collision detected by Ligo that produced evidence that enough energy was released to form gold and other heavy metals. 

From the MANTRA everything is a quantum fluctuation, what caused the original quantum fluctuation? Is space highly unstable popping out virtual particles and absorbing them continuously? I understand time becomes a bit funny inside a black hole how would the lifetime of virtual particles be affected inside a blackhole? Muon lifetimes are affected by gravity, why not virtual particles. Bose Einstein condensates act as one entangled particle at near absolute zero. Could virtual particles in space do the same thing and form the first stable quantum fluctuations, and then gravity and then black holes and then heat and then big bangs?

The answer I know will be Nope but why not?

 

On 11/26/2017 at 10:11 PM, Mordred said:

OK I can see I have a bit of work cut out for me here. OK lets start with the problem of "Where does the energy come from". Well energy is simply a property that is defined by the ability to perform work. So it doesn't need to come from anywhere, it doesn't need to be created but simply emerges for various applications.

Start with Potential energy: "In physics, potential energy is the energy possessed by an object because of its position relative to other objects"

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

So by merely changing the position of one object compared to another I change the potential energy....

Kinetic energy: "In physics, the kinetic energy of an object is the energy that it possesses due to its motion"

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

Now what about mass?

Mass "is both a property of a physical body and a measure of its resistance to acceleration (a change in its state of motion) when a net force is applied"

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

So looking at those statements Does energy need to exist in the first place or does it simply develop as field anisotropies develop via potential differences between two or more measurement points ? much like voltage in electrical circuits?

Now as for the universe temperature. There is a very important relation between the density of particles in a given volume. This is simply the ideal gas laws in play. Yes pv=NRT. If you take x number of particles and compress them, the temperature will increase. To do otherwise would violate the laws of thermodynamics...

In Cosmology applications the temperature follows a very interesting relation it is the inverse of the scale factor.

a=1T that is a direct application of those ideal gas laws I just mentioned above.

The question of the laws of physics becoming invalid in BH's depends on how one defines those laws of physics. In mathematical precision its when symmetry can no longer be applied. It would take a bit to fully describe that under math as it requires an understanding of various notations many aren't accustomed to but if you like I can readily post the mathematical descriptive.

 

I know you are good at maths, I graduated 20 years ago with an engineering degree and a masters, but like most use little of what I studied in the many roles I have had. When I read what you have written it comes back, (I did not like the Schrodinger equation its a monster). If you can explain why with enough pressure and heat a black hole wont convert its matter to pure energy and explode it would be seriously appreciated. 

Edited November 28, 2017 by interested
last comment

[Strange]

35 minutes ago, interested said:

I see I am excelling myself -20 points for wondering about what is inside a black hole so far.

I guess the negative points are not for "wondering" but for rejecting answer based on science and making up your own based on .... well, nothing beyond personal preference. 

36 minutes ago, interested said:

If enough matter is compressed inside a black hole the temperatures will match those prior to the plank time of the big bang 

I thought the temperature had always been the same.

37 minutes ago, interested said:

Matter will become pure energy in the form of radiation due to temperature and pressure inside a blackhole that is big enough. 

There is no such thing as "pure energy" but never mind. But, yes, the matter could all turn into radiation - we have no way of knowing. But that doesn't make much difference. It still contributes to the mass of the black hole in the same way (remember, mass and energy are equivalent). And it still has no path away from the centre of the black hole.

38 minutes ago, interested said:

How is this different to a big bang?

Because there is (as far as we know, currently) no way for the black hole t explode as you suggest. One way of seeing the difference is that the singularity in the Big Bang model is in the past while the singularity in a black hole is in the future of any mass (or energy) inside the event horizon (because space-time becomes so curved that the radial dimension is swapped with the time dimension).

[Not that there is any reason to think that singularities exist in either case.]

Quote

The mass is consumed converted into energy, gravity collapses damn thing explodes releasing tonnes of energy like a big bang, if the black hole is spinning then the energy will be released in the form of a spiral galaxy.

Galaxies were formed much, much later than any Big Bang event [and there is no evidence for such an event anyway].

Simulations of how the matter in the early universe cooled and formed large scale structures show that galaxies are formed by the gravitational collapse of matter, not by explosions.

43 minutes ago, interested said:

Blackholes as I understand have not been observed colliding as yet, but in theory they could, as did recently with the neutron star collision detected by Ligo that produced evidence that enough energy was released to form gold and other heavy metals. 

LIGO has detected 5 (I think) black hole collisions so far.

[Note that the gold and other heavy elements were created from the matter (and energy) already resent. It is not being created "from nothing".]

[interested]

8 minutes ago, Strange said:

I thought the temperature had always been the same.

I learned the annoying tactic of posting from reading your posts. Anyway the CBR is always the same temperature, ha ha.

The temperature inside the black hole will increase as Mordred pointed above.

10 minutes ago, Strange said:

There is no such thing as "pure energy" but never mind. But, yes, the matter could all turn into radiation - we have no way of knowing. But that doesn't make much difference. It still contributes to the mass of the black hole in the same way (remember, mass and energy are equivalent). And it still has no path away from the centre of the black hole.

Wordology, I thought it was obvious I was talking about radiation. If the big bang theory is half based on fact then we know it will explode.

Will the momentum of the radiation add to the mass of the blackhole ? 

Will the momentum of the radiation prior to the plank time have mass?  in BB

Does energy have mass? if so how the did the BB having infinite energy approximately Bang.

18 minutes ago, Strange said:

Because there is (as far as we know, currently) no way for the black hole t explode as you suggest.

OH so I might be correct ha ha.

 

20 minutes ago, Strange said:

Galaxies were formed much, much later than any Big Bang event [and there is no evidence for such an event anyway].

Simulations of how the matter in the early universe cooled and formed large scale structures show that galaxies are formed by the gravitational collapse of matter, not by explosions.

Yes we know this from the BB theory, we also know from observation they rotate and have black holes at their centre, and planets contain heavy metals that can only have formed from explosive events like perhaps Black holes colliding as well as extinct stars colliding. Stars are not hot enough on their own to generate anything heavier than iron as we know.

 

25 minutes ago, Strange said:

LIGO has detected 5 (I think) black hole collisions so far.

[Note that the gold and other heavy elements were created from the matter (and energy) already resent. It is not being created "from nothing".]

I do not recall reading about the black holes colliding, I thought I had but when I googled it again this morning I could not find reference to it. Thanks for that I will look again.

Yes I know it takes matter to make matter, but that does not matter. 

The interesting thing is I might not be a million miles away from the truth.

1 hour ago, interested said:

From the MANTRA everything is a quantum fluctuation, what caused the original quantum fluctuation? Is space highly unstable popping out virtual particles and absorbing them continuously? I understand time becomes a bit funny inside a black hole how would the lifetime of virtual particles be affected inside a blackhole? Muon lifetimes are affected by gravity, why not virtual particles. Bose Einstein condensates act as one entangled particle at near absolute zero. Could virtual particles in space do the same thing and form the first stable quantum fluctuations, and then gravity and then black holes and then heat and then big bangs?

You never commented on the above. 

6 hours ago, MigL said:

 

Maybe that's your problem, Interested, you confuse political OPINION with scientific FACTS and OBSERVATIONS.

Bitchy

What problem, I might not be to far from the truth. Confusing scientific theories with with actual facts or observations has gone on for millennia. I am however beginning to think the old testament might be correct, in the beginning there was light or maybe quantum fluctuations

Thanks for the heads up on Hawking radiation by the way, you feisty old git. Ah Ah

 

[Strange]

1 minute ago, interested said:

If the big bang theory is half based on fact then we know it will explode.

The Big Bang was not really an explosion. This is another key difference from your idea. Even if a black hole could explode and send huge amounts of mass and energy into space, that is not what the Big Bang model describes.

The Big Bang model does not say: there was empty space and then something exploded to fill it with matter (and energy). 

The Big Bang model does say: the universe has always been completely full of matter and energy. The universe has expanded and cooled over time. As a result, we get the CMB and the formation of structures like stars and galaxies.

5 minutes ago, interested said:

Will the momentum of the radiation add to the mass of the blackhole ?

It will contribute. But that momentum can only have come from the mass and energy that was already present. So it isn't increasing the mass.

6 minutes ago, interested said:

Will the momentum of the radiation prior to the plank time have mass?  in BB

We don't really know anything about the universe that early on. But if we assume the same rules apply, then momentum, energy and mass all contribute to gravitational effects and can all be considered equivalent to mass.

7 minutes ago, interested said:

Does energy have mass?

It is equivalent to mass (e=mc²). So, for example, (as noted in another thread) hot water has more mass than cold water because it has more energy. If you were to trap photons (no mass) in a box, the box would have more mass because of the energy of the photons.

8 minutes ago, interested said:

if so how the did the BB having infinite energy approximately Bang.

We don't know if it had infinite energy. If the universe is infinite, then (presumably) it did. If the universe is finite, then it didn't.

10 minutes ago, interested said:

I do not recall reading about the black holes colliding, I thought I had but when I googled it again this morning I could not find reference to it. Thanks for that I will look again.

http://www.skyandtelescope.com/astronomy-news/ligo-sees-smallest-black-hole-binary-yet-1611201723/

10 minutes ago, interested said:

You never commented on the above. 

I don't have much to say. Not everything is a quantum fluctuation. And I don't know how quantum fluctuations would be affected inside a black hole. My guess is, not much. Other than by gravitational time dilation - but as that depends on the observer and we cannot observe it, it seems a bit irrelevant.

[MigL]

Something that should be cleared up...

Both mass and energy are properties of the system, more exactly, in a static situation, energy is related to the configuration of the system.
As we wind the film back towards t=0, we get to the time of the Electroweak symmetry break, which precipitated out the Higgs field.
It is the interaction of this field with certain particles which gives them the property of mass.
At any time before the electroweak symmetry break, the concept of mass is undefined.

If you are going to discuss conditions at about the Planck time, you are talking about energy ( the system's configuration ), not mass, as there is no such thing ( yet ).

And contrary to what you may believe, there is no 'compression' once a Black Hole throws up an event horizon. The path followed, as Strange has pointed out numerous times, is not a path through space, but a path forward in time. There is no compression leading to heating as with a gas. The entropy of a BH is determined by the area of its event horizon ( see Hawking/Bekenstein ), and from the entropy we can determine the temperature, which for massive BHs is close to abs. zero. Temperature increases as BHs get smaller, such that only micro BHs that have high temps.

[interested]

Continuing my line of thought the Energy of photons is inertia, and not mass, E=mc^2+pv, the photons energy is due to inertia only. 

The photons energy can be absorbed by other particles, but once there are no particles, to absorb the energy what happens with the inertia, what happens to gravity inside the blackhole. I know the path of photons is bent by gravity, which is caused by the action of mass on space, but what happens when the mass disappears, can photons alone inside a black hole cause gravity.

15 hours ago, MigL said:

If you are going to discuss conditions at about the Planck time, you are talking about energy ( the system's configuration ), not mass, as there is no such thing ( yet ).

I know and that energy is in the form of light ie radiation.

15 hours ago, MigL said:

And contrary to what you may believe, there is no 'compression' once a Black Hole throws up an event horizon. The path followed, as Strange has pointed out numerous times, is not a path through space, but a path forward in time. There is no compression leading to heating as with a gas. The entropy of a BH is determined by the area of its event horizon ( see Hawking/Bekenstein ), and from the entropy we can determine the temperature, which for massive BHs is close to abs. zero. Temperature increases as BHs get smaller, such that only micro BHs that have high temps.

So you believe not all things entering a BH do not gravitate towards a singularity somewhere in the middle and get squeezed. Big BHs do not get hot, but small BHs have high temperatures. Can you direct me to the difference in scales we are talking about here, have both types of BHs in question been detected.

On 11/28/2017 at 12:06 PM, Strange said:

The Big Bang was not really an explosion. This is another key difference from your idea. Even if a black hole could explode and send huge amounts of mass and energy into space, that is not what the Big Bang model describes.

The Big Bang model does not say: there was empty space and then something exploded to fill it with matter (and energy). 

The Big Bang model does say: the universe has always been completely full of matter and energy. The universe has expanded and cooled over time. As a result, we get the CMB and the formation of structures like stars and galaxies.

It is not really my idea the idea of a bouncy black hole has been around for some time, which I know you are aware off.

But here are a couple of links for anyone who is interested.

https://phys.org/news/2017-11-physicist-explores-possibility-vestiges-universe.html?utm_source=nwletter&utm_medium=email&utm_campaign=daily-nwletter 

https://phys.org/news/2013-05-theorists-loop-quantum-gravity-theory.html#nRlv

I strongly suspect the concept of before the Plank time and infinite energy levels (temperatures)  are just philosophical concepts, they can never be reached or studied. Also Singularities are mathematically inconveniences and do not exist ie are not a physical fact.

Space is constantly expanding between galaxies as pointed out by hubble and is due to Dark energy which is possibly caused by quantum fluctuations in space pushing slowly increasing the amount of space. The Casimir effect is interesting from this point of view because a restriction in the amount of quantum fluctuations pulls the plates together. Increasing quantum fluctuations cause space to expand, restricting the amount of fluctuations causes it to contract, like gravity. Ie Space flows into a BH's pulling them together or at some point space is expanding enough to drive them apart. Is Gravity caused by the absorption and emission of random quantum fluctuations in space and not mathematically pleasing gravitons or equations. Space itself may be flat, and not curved although relativity states it is etc, I posted something on this under dark matter thread not mine but no one commented, I also think someone duplicated it under news, ie no dark matter if space is flat. 

Thank you for the responses.

I guess there is enough above to attract some derision. 

[Strange]

4 minutes ago, interested said:

It is not really my idea the idea of a bouncy black hole has been around for some time, which I know you are aware off.

But here are a couple of links for anyone who is interested.

 

 

These are both variations of the "big bounce" model which gets rid of the singularity (but has nothing to do with black holes).

7 minutes ago, interested said:

Also Singularities are mathematically inconveniences and do not exist ie are not a physical fact.

I think pretty much everyone would agree with that.

8 minutes ago, interested said:

Space is constantly expanding between galaxies as pointed out by hubble and is due to Dark energy

The expansion happens without dark energy. Dark energy is suggested to explain the observed and unexpected acceleration of expansion.

[interested]

3 hours ago, Strange said:

These are both variations of the "big bounce" model which gets rid of the singularity (but has nothing to do with black holes).

I think pretty much everyone would agree with that.

The expansion happens without dark energy. Dark energy is suggested to explain the observed and unexpected acceleration of expansion.

I am pretty sure Black holes are mentioned "Black holes are the starting point of Neves' investigations into a theoretical "Bouncing universe." "

They also get rid of the big bang concept. Black holes we know exist, removing a singularity allows them to bounce. 

Yes I know it is accelerating, I also know that this should reduce the temperature of CBR if the Big bang theory is correct. I think after the  plank time BB is based on testable physics, prior to the plank time things get a bit dodgy,and it looks like a reversal of what happens in a black hole. Expansion happens because it is increasing the amount of space at an accelerating space between galaxies due to dark energy. Using the mantra all things are quantum fluctuations, dark energy may be due to an increasing number of quantum fluctuations accelerating the expansion of space. 

Have you got any idea what Migl was on about whereby, big black holes are cold whereas little ones are hot. Is he just pointing out what is observed at the event horizon, or does he actually believe inside a big black hole is cold. 

Edited November 29, 2017 by interested

[Strange]

1 hour ago, interested said:

I am pretty sure Black holes are mentioned "Black holes are the starting point of Neves' investigations into a theoretical "Bouncing universe." "

Black holes are mentioned. But they are not involved in his model of the Big Bang.

1 hour ago, interested said:

They also get rid of the big bang concept.

They get rid of the singularity. There is still the universe expanding from an early hot dense state, aka the Big Bang model.

1 hour ago, interested said:

Yes I know it is accelerating, I also know that this should reduce the temperature of CBR if the Big bang theory is correct. I

It is expansion that causes the cooling of the universe (as seen in the CMB) not acceleration.

Quote

Expansion happens because it is increasing the amount of space at an accelerating space between galaxies due to dark energy.

I hate to appear picky and banging away at the same point, but the details are important (this is science after all).

Expansion happens because of the distribution of mass-energy in the universe. This increases the amount of space between galaxy [clusters] at a constant rate.

Dark energy causes the rate of expansion to accelerate. We would have (and did have) expansion even without the effects of dark energy.

1 hour ago, interested said:

Have you got any idea what Migl was on about whereby, big black holes are cold whereas little ones are hot. Is he just pointing out what is observed at the event horizon, or does he actually believe inside a big black hole is cold.

It is the temperature of the event horizon. Which is the only thing we can know about.

In the "regular black hole" described in the link you provided, there is no singularity and therefore no concentration of matter at the centre. I don't know what this says about the theoretical temperature inside the event horizon. It will presumably be lower than the standard model of a block hole, that's all I can say.

[beecee]

OK, I have come into this late, so bear with me if you will. Any errors, alterations and/or corrections welcome:                                                                                                                              The stages to a BHs creation is firstly the radiative pressure of nuclear fusion, being overcome by gravity, secondly as the core gets denser, EDP (electron degeneracy pressure) and NDP (Neutron degeneracy pressure) are overcome and a stage is reached when the Schwarzchild radius is reached and an EH formed. GR tells us that at this point further collapse is compulsory. While we are never able to get any information from inside a BH, we can reasonably and logically assume due to the compulsory collapse edict, that collapse continues until at least the quantum/Planck level where the laws of physics and GR are invalid, as far as we know. This is one definition of a BH singularity, the other being that collapse continues until a singularity of infinite density and spacetime curvature is formed.   Most cosmologists now do not accept the latter version, which means that the singularity should be defined as where GR and the laws of physics are invalid. So a surface or conglomeration of sorts exists at this quantum/Planck level.

Nothing but nothing ever crosses the EH from inside to outside as all matter/energy simply only has a choice of one path to take, that is to the singularity. Even Hawking radiation does not entail any particle/energy crossing that EH from inside to outside.

In essence a BH is simply critically curved spacetime with a singularity as defined by the non applicability of our laws and GR, so to speak of BH density is really inappropriate. 

On recent posts, the "bouncing universe"hypothetical, or as it was called in the fifties, "The Oscillating" model does not necessarilly invalidate the BB, rather it entails the BB, and simply extends the zones of applicability beyond into specualtive regions and physics.

OK, now some queries..

7 hours ago, Strange said:

The expansion happens without dark energy. Dark energy is suggested to explain the observed and unexpected acceleration of expansion.

I agree...My question is is the expansion simply a result of the impetus from Inflation and whatever made spacetime to start evolving/expanding. This seems reasonable to me due to the scenario that the gravity from the mass/density in the early universe, was acting to slow down the overall expansion rate, but as the expansion continued, the mass/energy density was reduced, and consequently expansion then started accelerating as the cause of expansion is constant over all spacetime.

 

The second query concerns my thoughts on why the BB is overwhelmingly accepted as the best model we have...The way I see it, other then the usual pillars of cosmology which it aligns with, such as the CMBR, abundance of lighter elements, the observed expansion, etc, the fact that it seems to fit hand in glove with GR, a powerful freind and ally I would suggest. 

 

The third query is  are there any errors in my preamble?

 

Edited November 29, 2017 by beecee

[Strange]

8 minutes ago, beecee said:

I agree...My question is is the expansion simply a result of the impetus from Inflation and whatever made spacetime to start evolving/expanding.

That is my understanding. A homogenous distribution of matter (as in the early universe and, approximately, now) cannot be stable under GR. It will either move apart or collapse. The initial impetus means it is moving apart. It was originally thought that this would slow, because of gravity, but it turned out to be accelerating.

10 minutes ago, beecee said:

The second query concerns my thoughts on why the BB is overwhelmingly accepted as the best model we have...The way I see it, other then the usual pillars of cosmology which it aligns with, such as the CMBR, abundance of lighter elements, the observed expansion, etc, the fact that it seems to fit hand in glove with GR, a powerful freind and ally I would suggest. 

Exactly. LeMaitre (who published Hubble's Law before Hubble) used GR to show there should be expansion and then used the redshift-distance relation to calculate the rate of expansion. Others then came up with all the other predictions that have been confirmed over and over.

 

[interested]

40 minutes ago, beecee said:

The second query concerns my thoughts on why the BB is overwhelmingly accepted as the best model we have...The way I see it, other then the usual pillars of cosmology which it aligns with, such as the CMBR, abundance of lighter elements, the observed expansion, etc, the fact that it seems to fit hand in glove with GR, a powerful freind and ally I would suggest. 

How does BB fit with GR hand in glove unless the two things are the same thing. Black holes according to relativity do not explode, BB does. You have stated above that matter is continually crushed down becoming more dense particles. What I was suggesting that seems reasonable to me is that matter entering a black hole may break down into radiation if heated enough, we know two particles cant occupy the same space, whereas bosons can. If all or part of the mass inside a black hole was converted to radiation with just inertia, does it not look like a BB after the plank time with no need for the laws of physics to break down.

What I was trying to look at is the similarity between the big bang and what may be happening inside a black hole, ie the Blackhole reversing the Big Bang, by at sufficiently high temperatures converting matter back into radiation. Would a black hole that hypothetically converted it mass into radiation not fulfill the requirements to be a BB.  

Some body gave me a book to read on explosives some years ago to create strong magnetic fields, and some info on Plasma was included. 

A lightning Plasma will reach immense temperatures, at the point where the plasma implodes after a lightning discharge. It is the implosion where things really get hot. A Black hole collapsing is going to get hot also, perhaps hot enough to break the matter down to matter and antimatter, and turn into gamma rays as was observed by NASA coming from lightning clouds and possibly also coming from neutron stars or something a bit bigger and hotter internally perhaps. Although the temperature may not be visible on the event horizons of the bigger black holes. 

The 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. What happens if the mass in the sphere is converted to radiation, ie high energy gamma rays, having only inertia and no mass. 

I was kind of hoping someone could explain why the mass wont just convert back to radiation at high enough pressures and temperatures, and replicate a BB. 

It makes sense to me any way. 

[Strange]

1 minute ago, interested said:

How does BB fit with GR hand in glove unless the two things are the same thing.

There are many possible solutions to the Einstein Field Equations (GR). The FLRW metric used in the Big Bang model is one of those solutions that appears to match the observed universe very well.

Another set of solutions are those that describe black holes of various types. (And the fact that these solutions are completely different from that used to describe the universe, is another reason that the Big Bang is not like a black hole.)

4 minutes ago, interested said:

I was kind of hoping someone could explain why the mass wont just convert back to radiation at high enough pressures and temperatures, and replicate a BB. 

We would need a quantum theory of gravity to really know what happens to mass. But maybe it does turn into radiation. That would make no difference at all. It wouldn't change anything about the black hole (which is why we can't know what happens inside a black hole).

And it can't replicate a Big Bang because (1) we know of no way for anything to get out of a black hole and (2) even if a black hole exploded, that is not the same as the Big Bang which was not an explosion.

 

[I have a strong sense of deja vu.]

[interested]

It is by the action of going around in circles that may be creating an appearance of Deja Vu but the subject becomes clearer and more polished each time I go around the circle.   

https://gizmodo.com/what-was-our-universe-like-before-the-big-bang-1791889926 A bit of speculation from some for mild amusement.

If there is a theory out there that predicts matter will eventually break down into radiation when subjected to pressure and temperature at some critical density and temperature then a black hole would resemble the early stages of a big bang.  

Edit 

Oh and a rotating black hole will have a much smaller radius for radiation to get out of, and as a black rotating collapse it will spin faster and faster with anything flying out of its event horizon go spiraling of into space

 

Edited November 29, 2017 by interested
terrible grammar

[Strange]

11 minutes ago, interested said:

It is by the action of going around in circles that may be creating an appearance of Deja Vu but the subject becomes clearer and more polished each time I go around the circle.   

As long as we are moving forward as we go round in circles, I'm happy!

11 minutes ago, interested said:

If there is a theory out there that predicts matter will eventually break down into radiation when subjected to pressure and temperature at some critical density and temperature then a black hole would resemble the early stages of a big bang.

1. Nothing can get out of a black hole.

2. It makes no difference if the inside of the black hole is matter or radiation: it can't get out and the mass of the black hole is the same.

3. A black hole has the mass of a few stars (or possibly a few million). The universe has billion of billions of billions of stars. So there isn't enough mass in the black hole to create a universe.

4. A black hole (whether exploding or not) does not resemble the early universe. A black hole is a concentration of mass within the universe (in the case of a Schwarzschild back hole, an empty universe). The universe, by contrast, is (and always has been) entirely full of matter and radiation.

 

Edited November 29, 2017 by Strange

[interested]

1 minute ago, Strange said:

As long as we are moving forward as we go round in circles, I'm happy!

1. Nothing can get out of a black hole.

2. It makes no difference if the inside of the black hole is matter or radiation: it can't get out and the mass of the black hole is the same.

3. A black hole has the mass of a few stars (or possibly a few million). The universe has billion of billions of billions of stars. So there isn't enough mass in the black hole to create a universe.

4. A black hole (whether exploding or not) does not resemble the early universe. A black hole is a concentration of mass within the universe (in the case of a Schwarzschild back hole, an empty universe). The universe, by contrast, is (and always has been) entirely full of matter and radiation.

 

1) What is a nothing, how does it get out of a black hole 

2) Radiation has no mass it only has inertia. Can a black hole consist of just radiation, does the gravity inside a black hole not require mass for it to work. Radiation has no mass only energy.    

3) I completely agree the universe is really really big and each galaxy appears to have black holes at their centre, and there are lots and lots of black holes some of which appear hot and release radiation from the event horizon.

4) I was told to use the Mantra everything is quantum fluctuations > Space has always been full of quantum fluctuations, the early universe must have been full of them, and Dark energy may be caused by quantum fluctuations, the Casimir effect indicates gravity might be caused by the restriction or absorption of quantum fluctuations.

Could Quantum fluctuations in an expanding space at absolute zero could also be the source of dark matter? Could also virtual particles ordinarily short lived falling into a  blackhole exist long enough to be compressed with other virtual articles to become a real particle? Perhaps not

 

 

[Strange]

Just now, interested said:

2) Radiation has no mass it only has inertia. Can a black hole consist of just radiation, does the gravity inside a black hole not require mass for it to work. Radiation has no mass only energy. 

Mass and energy are equivalent. In fact, mass doesn't appear at all in the Einstein Field Equations. It is represented by the equivalent energy.

A black hole has only three properties: mass, electric charge (normally zero) and angular momentum (normally non-zero). Whatever happens to the matter after it falls in cannot change these.

1 minute ago, interested said:

Could Quantum fluctuations in an expanding space at absolute zero could also be the source of dark matter? 

Quantum fluctuations are the same throughout space. Dark matter is concentrated in and around galaxies.

[Dubbelosix]

Represented by a stress energy tensor, which is related to the geometry of the system. Nevertheless, The black hole dynamics are indeed established by three factors the mass, the charge and the angular momentum. The last two are mutually complimentary. That is, a spinning black hole produces a charge. Non-rotating black holes have in its earliest terminology been classed as ''stagnant black holes'' - earlier than that, the black hole used to be called frozen stars, I much prefer that terminology

 

Edited November 29, 2017 by Dubbelosix

[interested]

6 minutes ago, Strange said:

Mass and energy are equivalent. In fact, mass doesn't appear at all in the Einstein Field Equations. It is represented by the equivalent energy.

A black hole has only three properties: mass, electric charge (normally zero) and angular momentum (normally non-zero). Whatever happens to the matter after it falls in cannot change these.

Quantum fluctuations are the same throughout space. Dark matter is concentrated in and around galaxies.

On the subject of Dark matter I was just looking for something on bosons and stumbled across this link on exotic stars. All competely theoretical of course, but interesting never the less the boson star is what drew my attention but dark matter is also discussed and some exotic states of matter which partially answer my earlier question. https://en.m.wikipedia.org/wiki/Exotic_star#Boson_stars

[Strange]

1 minute ago, Dubbelosix said:

the charge and the angular momentum. The last two are mutually complimentary. That is, a spinning black hole produces a charge.

I didn't know that. Do you have a reference?

[Dubbelosix]

If memory serves well, the Kerr Black hole is the rotating solution of the Schwarzschild black hole (non-rotating variation) which has no charge. 

[interested]

1 minute ago, Strange said:

I didn't know that. Do you have a reference?

ditto how does a spinning black hole produce a charge if nothing can get out, do they have a magnetic field no