Black hole?

[Strange]

22 hours ago, interested said:

Phase transitions took place during the big bang, is it likely these are reversed inside a black hole due to pressure and temperature?

One difference is that the expansion of the universe is the same in all directions (so things become increasing compressed as we go back in time). In the case of a black hole, material undergoes spaghettification, which means stretched in one direction and compressed int the other two. As a result (if I remember correctly) the volume stays constant. So not the same  compression, heating, etc.

[interested]

15 hours ago, Mordred said:

Its questionable whether or not some of those phase transitions are reversible under compression as opposed to expansion. A large part of the reason being availability of the correct particle species during the transition stages.

 The process of nucleosynthesis coupled with inflation isn't nearly the same as compression. So the sequence of nucleosynthesis may not be reversible as you won't have the supercooling then reheating phase transitions via compression. That in and of itself will alter the applicable phase transitions

I am aware I may be pushing the Mantra "all things are quantum fluctuations and or excitations" beyond breaking point, and am aware it is best applied only when zooming in to the very small scale. Other models are better suited when zooming out. However staying zoomed in, what at the quantum level constitutes a gravitational wave or maybe dark energy? Could it be the absorption and emission of virtual particles?

What has caught my attention in the recent BH merger detected by Ligo is the loss of 3 solar masses. This is passed of as being converted to gravitational energy.  

Where did the mass go, how was it converted into a gravity wave or nothing inside the BH. The gravitional attraction from the BH reduced by 3 solar masses after the merger, no mass escaped the BH, where did the mass go?  Was it driven out of existence via some phase transition from quantum excitations to fluctuations. 

How are quantum fluctuations and excitations affected by extreme gravity?  Even gravitons if they exist must flow into a Black hole not out, as will all other forms of quantum fields. So where did the 3 solar masses go?

 

[Strange]

4 minutes ago, interested said:

what at the quantum level constitutes a gravitational wave or maybe dark energy?

No one can answer that until we have a theory of quantum gravity. 

 

6 minutes ago, interested said:

So where did the 3 solar masses go?

Into the energy of the gravitational waves. 

[interested]

3 hours ago, Strange said:

Into the energy of the gravitational waves. 

Three solar masses of energy escaped from inside a black hole as gravitational energy. Here is me being led to believe nothing gets out except maybe Hawking radiation. 

How was the 3 solar mass reduction detected in the merged BH?

Could the 3 solar masses have been Dark Matter which did not need to escape the BH, because it was not inside the BH?

3 hours ago, Strange said:

No one can answer that until we have a theory of quantum gravity. 

How are theories on quantum gravity coming on, do any allow for a big bounce, a bit like a big bang.

Is Quantum loop gravity able to explain anything about BH's yet.

 

 

18 hours ago, Mordred said:

The process of nucleosynthesis coupled with inflation isn't nearly the same as compression. So the sequence of nucleosynthesis may not be reversible as you won't have the supercooling then reheating phase transitions via compression. That in and of itself will alter the applicable phase transitions

Do you know of any papers out lining what phase transitions may be applicable. How is mass converted to a gravity wave, radiating outwards from a BH at light speed.  

Edited December 17, 2017 by interested

[Strange]

32 minutes ago, interested said:

Three solar masses of energy escaped from inside a black hole as gravitational energy. Here is me being led to believe nothing gets out except maybe Hawking radiation. 

The gravitational waves originate in the space-time outside the black holes as it is “stirred up” by the orbiting black holes. 

34 minutes ago, interested said:

How was the 3 solar mass reduction detected in the merged BH?

I’ll find you a link and summary of the parameter estimation paper when I get home. 

36 minutes ago, interested said:

Is Quantum loop gravity able to explain anything about BH's yet.

I don’t know. But I was going to say that s better question would be: how are black holes represented in string theory, LQG, CDT, etc? (I don’t know the answer.)

 

[interested]

On 12/17/2017 at 3:51 PM, Strange said:

I don’t know. But I was going to say that s better question would be: how are black holes represented in string theory, LQG, CDT, etc? (I don’t know the answer.)

I stumbled across these links whilst trying to find out what entanglement had to do gyroscopes and thought of your question. Perhaps Verlinde is getting close to being able to answer your questions, he does not need dark matter to explain the movement of 30000+  galaxies. 

https://phys.org/news/2016-12-verlinde-theory-gravity.html

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

[Strange]

I think it is an interesting idea, but it seems to be a long way from being confirmed. Maybe a step in the right direction, though.

37 minutes ago, interested said:

he does not need dark matter to explain the movement of 30000+  galaxies

Neither of your links say that, as far as I can tell. They both mention tests of gravitational lensing on a similar number of galaxies.

[interested]

10 hours ago, Strange said:

Neither of your links say that, as far as I can tell. They both mention tests of gravitational lensing on a similar number of galaxies.

Quoting  from the second link

"Importantly, the theory also explains (without invoking the existence of dark matter and its accompanying math featuring new free parameters that are tweaked to obtain the desired outcome) why galactic rotation curves differ from the profile expected with visible matter.

The theory of entropic gravity posits that what has been interpreted as unobserved dark matter is actually the product of quantum effects that can be regarded as a form of positive dark energy that lifts the vacuum energy of space from its ground state value

"

Gravity is caused by Quantum effects, ie Quantum fluctuations and or excitations like everything else in the known universe. It may be a long way from being confirmed but like you say it may be a step in the right direction, and does not need a random amount of never detected dark matter(new free parameters) to make the theory work and explains gravitational lensing. 

[Strange]

3 minutes ago, interested said:

Quoting  from the second link

Yes, but nothing about that being tested against 30,000 galaxies. That was gravitational lensing.

The next test is to see if it can also explain all the other evidence for dark matter.

[interested]

3 minutes ago, Strange said:

Yes, but nothing about that being tested against 30,000 galaxies

If you watch the Verlinde video given by the lady with glasses she mentions the 30000+ galaxies and gravitational lensing effects having been explained.

 

6 minutes ago, Strange said:

The next test is to see if it can also explain all the other evidence for dark matter.

gravitational lensing is one of the corner stones of the support for dark matter. What other evidence are you talking about?

[Strange]

1 minute ago, interested said:

If you watch the Verlinde video given by the lady with glasses she mentions the 30000+ galaxies and gravitational lensing effects having been explained.

Yep. Not rotation curves. (I'm not saying the theory can't explain rotation curves - I have no idea - just pointing out that the "30,000 galaxies" is about lensing not speeds.)

Quote

gravitational lensing is one of the corner stones of the support for dark matter. What other evidence are you talking about?

• Does his theory predict the movements of galaxy clusters correctly, as well as speeds within galaxies
• Simulations of the formation of the large scale structure of the universe require dark matter to produce results consistent with the real universe; would these work equally well with his modified gravity theory
• The bullet cluster (and others) where it seems the dark matter (seen by gravitational lensing) has separated from the visible matter - not sure how just modifying gravity can do that
• The cosmic microwave background contains patterns that can be explained by the presence of dark matter in the early universe

More detail here, for example: https://medium.com/starts-with-a-bang/five-reasons-we-think-dark-matter-exists-a122bd606ba8

[interested]

On 12/20/2017 at 9:33 AM, Strange said:

 

More detail here, for example: https://medium.com/starts-with-a-bang/five-reasons-we-think-dark-matter-exists-a122bd606ba8

The link does not appear to work, my internet is slow this morning so the problem could be at my end.

On 12/20/2017 at 9:33 AM, Strange said:

The cosmic microwave background contains patterns that can be explained by the presence of dark matter in the early universe

How does dark matter influence cosmic back ground radiation when it only affects gravity? are you saying it is the cause of CMB? 

I understand CMB is pretty uniform everywhere. Does the bullet cluster have more or less CMB because of separation from dark matter?

On 12/20/2017 at 9:33 AM, Strange said:

Simulations of the formation of the large scale structure of the universe require dark matter to produce results consistent with the real universe; would these work equally well with his modified gravity theory

Adding random amounts of Dark Matter to make large scale Simulations agree with what is observed, implies the model used in the simulation of larger scale structures may be wrong not that dark matter must exist.

On 12/20/2017 at 9:33 AM, Strange said:

Does his theory predict the movements of galaxy clusters correctly, as well as speeds within galaxies

I do not know what the limitations of his theory are yet, and do understand it is in the early days. He claims his theory successfully explains many affects currently attributed to dark matter and is based on purely observable effects, without the need for a random fudge factor, or dark matter to make it work. 

The theory is also based mainly on quantum theory, not relativity, quantum theory has proved to be extremely accurate on the small scale, why should it not ultimately be more accurate on the larger scale. Perhaps relativity has had its day and the universe is not mainly dark matter, but is in fact made up from Quantum effects or as Mordreds Mantra suggests"Quantum fluctuations and or excitations" 

 

 

[Strange]

29 minutes ago, interested said:

How does dark matter influence cosmic back ground radiation when it only affects gravity? 

To quote from the link above (still works for me, so may be your end):

"The patterns that we see in observations of the CMB were set up by competition between two forces acting on matter; the force of gravity causing matter to fall inward and an outward pressure exerted by photons (or particles of light). This competition caused the photons and matter to oscillate into-and-out-of dense regions. But if the Universe consisted partially of dark matter in addition to normal matter, that pattern would be affected dramatically. The existence of dark matter leaves a characteristic imprint on CMB observations, as it clumps into dense regions and contributes to the gravitational collapse of matter, but is unaffected by the pressure from photons."

Models of what we would expect to see based on the amount of dark matter we see today, matches the patterns in the CMB.

31 minutes ago, interested said:

Does the bullet cluster have more or less CMB because of separation from dark matter?

The B is for background so it is "behind" the bullet cluster; in other words, nothing to do with it.

32 minutes ago, interested said:

Adding random amounts of Dark Matter to make large scale Simulations ...

As with the CMB, it is not "random" amounts; it is the amount (proportion) that we see today.

 

[interested]

1 hour ago, Strange said:

But if the Universe consisted partially of dark matter in addition to normal matter, that pattern would be affected dramatically. The existence of dark matter leaves a characteristic imprint on CMB observations, as it clumps into dense regions and contributes to the gravitational collapse of matter, but is unaffected by the pressure from photons."

You may be right

But If gravity works as mentioned in the links above then dark matter may not be required,( or at least not as much dark matter). Matter causes Gravity which causes more matter to collapse into dense regions of matter, photons are affected by gravity and are diffracted by it causing gravitational lensing.

Dark Matter if it does not exist will not effect gravity, not even photons. If it does not exist and cant be detected, then  Verlindes theory might be correct. Or at least more correct than the existing theories.

[Strange]

1 minute ago, interested said:

Dark Matter if it does not exist will not effect gravity, not even photons. If it does not exist and cant be detected, then  Verlindes theory might be correct.

As long as it can explain the patterns in the CMB, the separation of dark matter and normal matter in the Bullet Custer (and others), and so on.

This article covers black hole mergers and the other subjects you are interested in: https://medium.com/starts-with-a-bang/dark-matter-winners-and-losers-in-the-aftermath-of-ligo-f34ffab04fcb

[interested]

5 hours ago, Strange said:

: https://medium.com/starts-with-a-bang/dark-matter-winners-and-losers-in-the-aftermath-of-ligo-f34ffab04fcb

Quoting from your link 

"It’s still too early to say exactly what dark matter is (and what it isn’t), but it’s very easy to see what’s looking better and what requires even more special pleading in the aftermath of the past two years. General Relativity has passed another, very stringent test with flying colors: gravitational waves are real, carry energy, have the properties (amplitude, frequency, redshift, polarization, etc.) they were predicted to have, and move precisely at the speed of light. Modified gravity theories where photons and gravitational waves follow different rules are highly constrained, and primordial black holes and WIMPs, particularly supersymmetric WIMPs, are looking less and less likely."

It seems that many types of dark matter have been ruled out, which we already new, it also suggests neutrinos might be a form of cold dark matter, which I think from the earlier thread on dark matter you and others ruled out, except perhaps Mordred. 

The main thing LIGO has been able to confirm is that gravitational waves definitely exist and travel at the speed of light. LIGO has not confirmed the existence of dark matter in any way. The fact that Einsteins theories predicted gravitational waves, does not by default confirm dark matter.  

The really interesting thing about the black hole mergers is the apparent loss of huge amounts of energy from inside the black holes ie 3 solar masses.

You previously stated nothing escapes from a black hole not even light, if this is true and Gravity is caused by the theoretical graviton (Quantum excitation ) a 2 spin boson, which must flow into the black hole, never to be seen again, or it is caused by Quantum fluctuations of some form or other that is absorbed by the black hole, both being spaghettified as they disappear over the event horizon. Depending on what idea you go for, gravity at the quantum level operates by absorption. For LIGO to detect a gravitation reduction in strength after the merger of two BH's by 3 solar masses, either the mass was destroyed or it never existed in the first place, (perhaps like dark matter). As the two BH's spiral together the Gravitational waves will peak at the merger and then as they collide 3 solar masses vanish. This causes a reduction in the gravitational strength of the BH, and LIGO detects a fluctuation in the gravity field in space, which travels at light speed away from the black hole, like a ripple in a pond. Prior to the LIGO results observing the neutron star merger, the speed of gravitational waves was uncertain, after this observation there can be no argument on the result. Gravitational waves travel at light speed.

6 hours ago, Strange said:

As long as it can explain the patterns in the CMB, the separation of dark matter and normal matter in the Bullet Custer (and others), and so on.

The Jury is out, and the verdict is definitely not clear, worse still there is a lot of popular science claims that things have been proven conclusively, when in actual fact they have not. 

[Strange]

3 hours ago, interested said:

It seems that many types of dark matter have been ruled out, which we already new, it also suggests neutrinos might be a form of cold dark matter

Not just neutrinos, but a (new) currently unknown type of massive neutrino.

3 hours ago, interested said:

The main thing LIGO has been able to confirm is that gravitational waves definitely exist and travel at the speed of light. LIGO has not confirmed the existence of dark matter in any way.

But it has, as the article points out, eliminated many (most) alternative gravity models and some forms of dark matter.

3 hours ago, interested said:

You previously stated nothing escapes from a black hole not even light, if this is true and Gravity is caused by the theoretical graviton (Quantum excitation ) a 2 spin boson, which must flow into the black hole, never to be seen again, or it is caused by Quantum fluctuations of some form or other that is absorbed by the black hole, both being spaghettified as they disappear over the event horizon. Depending on what idea you go for, gravity at the quantum level operates by absorption. 

This doesn't make much sense. I'm not sure what point you are trying to make.

If it helps (?) gravity would be mediated by virtual gravitons which are not particles and hence don't need to escape from the black hole.

Quote

As the two BH's spiral together the Gravitational waves will peak at the merger and then as they collide 3 solar masses vanish.

The energy is dissipated in the gravitational waves which are (largely) generated before the merger.

[interested]

20 hours ago, Strange said:

But it has, as the article points out, eliminated many (most) alternative gravity models and some forms of dark matter.

many most is not all, it is therefore not the only theory in play.

 

20 hours ago, Strange said:

If it helps (?) gravity would be mediated by virtual gravitons which are not particles and hence don't need to escape from the black hole.

They would like other particles be absorbed by the blackhole. This is the first I have heard that the graviton is a virtual particle, just goes to show it is a quantum fluctuation after all.

20 hours ago, Strange said:

The energy is dissipated in the gravitational waves which are (largely) generated before the merger.

OH I see! the energy E (mc^2+pv ) is converted from matter, into radiation, into gravitational waves before the two black holes merged, amazing. What decomposition process can do this, when the matter existed inside 2 separate black holes which merged, which nothing gets out of once it has entered the event horizon not even 3 solar masses or a photon. Please explain the decomposition process that allows 3 solar masses to be radiated away as gravitational waves. Is a gravitational wave virtual particles (Quantum fluctuations) are you saying the mass (Quantum excitations ) is converted into Quantum fluctuations during the merger. Maybe you are saying dark matter is Quantum fluctuations and not Quantum excitations? please clarify.

Seasons greetings  the days are getting longer already.

 

[Strange]

7 minutes ago, interested said:

They would like other particles be absorbed by the blackhole. 

Nope.

7 minutes ago, interested said:

Is a gravitational wave virtual particles (Quantum fluctuations) are you saying the mass (Quantum excitations ) is converted into Quantum fluctuations during the merger. Maybe you are saying dark matter is Quantum fluctuations and not Quantum excitations?

GR is a classical theory, so all of this is irrelevant.

 

[beecee]

39 minutes ago, interested said:

many most is not all, it is therefore not the only theory in play.

Discoveries as to this date have re-enforced GR. If there were any other "theories" still in play as you say, they would need to describe our observations more accurately then the incumbent model, and make even more verifiable predictions. I'm pretty sure if anything left in play could do that, then it would be pushed for all that it was worth as potentially, the author would be another Einstein. Remember, scientists/cosmologists everyday are doing their darndest to invalidate GR.

Quote

They would like other particles be absorbed by the blackhole. This is the first I have heard that the graviton is a virtual particle, just goes to show it is a quantum fluctuation after all.

Within GR, gravity [if this is your query, remembering I have come in late] does not need to get out of a BH. The gravitational field of any BH is a fossil field from the entity from which the BH formed. Also gravity is spacetime and is nonlinear, a property that in essence means gravity makes more gravity.

 

Quote

 What decomposition process can do this, when the matter existed inside 2 separate black holes which merged, which nothing gets out of once it has entered the event horizon not even 3 solar masses or a photon.

The gravitational radiation is being created as the BHs/NSs orbit each other cuminating in a final merger as detailed in the following two videos, one an excellent description by Brian Greene.

https://www.space.com/38288-gravitational-waves-detected-by-two-observatories.html

Quote

Please explain the decomposition process that allows 3 solar masses to be radiated away as gravitational waves. Is a gravitational wave virtual particles (Quantum fluctuations) are you saying the mass (Quantum excitations ) is converted into Quantum fluctuations during the merger. Maybe you are saying dark matter is Quantum fluctuations and not Quantum excitations? please clarify.

I was told long ago when discussing cosmology that one should not and cannot mix and try and interact two models. GR and quantum mechanics are incompatible.

 

It also seems at a quick glance that you still have questions re DM and how it fits in with GR.

https://phys.org/news/2017-12-dark-tale.html

An innovative interpretation of X-ray data from a cluster of galaxies could help scientists fulfill a quest they have been on for decades: determining the nature of dark matter.

The finding involves a new explanation for a set of results made with NASA's Chandra X-ray Observatory, ESA's XMM-Newton and Hitomi, a Japanese-led X-ray telescope. If confirmed with future observations, this may represent a major step forward in understanding the nature of the mysterious, invisible substance that makes up about 85% of matter in the universe.

"We expect that this result will either be hugely important or a total dud," said Joseph Conlon of Oxford University who led the new study. "I don't think there is a halfway point when you are looking for answers to one of the biggest questions in science."
Read more at: https://phys.org/news/2017-12-dark-tale.html#jCp
 

the paper:

https://arxiv.org/pdf/1608.01684.pdf

Consistency of Hitomi, XMM-Newton and Chandra 3.5 keV data from Perseus

Hitomi observations of Perseus with the Soft X-ray Spectrometer (SXS) provide a high-resolution look at the 3.5 keV feature reported by multiple groups in the Perseus cluster. The Hitomi spectrum – which involves the sum of diffuse cluster emission and the point-like central Active Galactic Nucleus (AGN) – does not show any excess at E ∼ 3.5keV, giving an apparent inconsistency with previous observations of excess diffuse emission. We point out that 2009 Chandra data reveals a strong dip in the AGN spectrum at E = (3.54 ± 0.02)keV (cluster frame) – the identical energy to the diffuse excess observed by XMM-Newton. Scaling this dip to the 2016 AGN luminosity and adding it to the diffuse XMM-Newton excess, this predicts an overall dip in the SXS field of view of (−5.9 ± 4.4) × 10−6 ph cm−2 s −1 at E = 3.54 keV – a precise match to the Hitomi data when broadened by the dark matter virial velocity. We describe models of Fluorescent Dark Matter that can reproduce this physics, in which dark matter absorbs and then re-emits 3.5 keV photons emitted from the central AGN.

Conclusions

We have argued that Hitomi, XMM-Newton and Chandra observations of the Perseus cluster at E ∼ 3.5keV show a remarkable degree of consistency. In particular, the Hitomi spectrum around 3.5 keV can be understood as the sum of a dip in the AGN spectrum at E = (3.54 ± 0.02) keV (observed by Chandra) with an excess in the diffuse cluster emission at an identical energy (observed by XMM-Newton and Chandra). We have described dark matter models that can give rise to this phenomenology. Sadly Hitomi is no longer able to contribute to observational efforts to understand the 3.5 keV line. We have emphasised that an accurate and clean spectrum of the NGC1275 AGN is crucial for understanding this phenomenon. Significant improvements on this can be made using operating satellites and with existing CCD technology. The best current spectrum was taken in 2009 by Chandra with the nominal frame time of 3 seconds. Given the AGN is now twice as bright, a further dedicated off-axis observation of NGC1275, operating with reduced frame time to minimise pileup, would give a substantial improvement over the 2009 data.

 

 

[swansont]

1 hour ago, interested said:

  What decomposition process can do this, when the matter existed inside 2 separate black holes which merged, which nothing gets out of once it has entered the event horizon not even 3 solar masses or a photon. Please explain the decomposition process that allows 3 solar masses to be radiated away as gravitational waves.

Is it the case that all of the mass energy of a binary BH is within the event horizons? 

[MigL]

The mass, angular momentum, charge ( and entropy ) are encoded on the size/surface of the event horizon.
Anything within the event horizon should be considered 'empty', at least until quantum gravity tells us otherwise.

[beecee]

On 11/21/2017 at 4:23 AM, Strange said:

Weirdly, part of their argument seems to be that scientists deny the existence of white holes because it sounds like "creation" (of matter, etc.) not because there is no evidence for them. But scientists accept the existence of black holes because ... liberals. Or something. 

White Holes and wormholes are predictions of the equations of GR, but as yet we have no evidence for their existence.

I did find this interesting piece.

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

In general relativity, a white hole is a hypothetical region of spacetimewhich cannot be entered from the outside, although matter and lightcan escape from it. In this sense, it is the reverse of a black hole, which can only be entered from the outside and from which matter and light cannot escape. White holes appear in the theory of eternal black holes. In addition to a black hole region in the future, such a solution of the Einstein field equations has a white hole region in its past.^[1]However, this region does not exist for black holes that have formed through gravitational collapse, nor are there any known physical processes through which a white hole could be formed. Although information and evidence regarding white holes remains inconclusive, the 2006 GRB 060614 has been proposed as the first documented occurrence of a white hole.

https://en.wikipedia.org/wiki/GRB_060614

GRB 060614 was a remarkable gamma-ray burst (GRB) detected by the Swift satellite on June 14, 2006 with puzzling properties, which challenge current progenitor models.^[1]

In particular, the lack of any bright supernova(SN) down to very strict limits and the vanishing spectral lags during the whole burst are typical of short GRBs, strikingly at odds with the long (102s) duration of this event and its origin in a galaxy 1.6 billion light years away in the constellation Indus.^[2]

In 2011, it was hypothesised that the burst was a white hole appearing for 102 seconds.^[3]

 

 

Edited December 22, 2017 by beecee

[MigL]

White holes only appear in 'maximally extended' solutions to the field equations.
That is, only where there are extended paths that particles can follow, without running into an 'edge' of space-time.

To me, they seem to be an artifact of observer frame dependency, and not a physical event.
And why would they be short-lived, in the order of hundreds of seconds; should they not last as long as BHs do since the event horizons are 'related' ?

I would more likely assume your GRB was related to the final 'evaporation' of a small, primordial BH, rather than a white hole, BeeCee.

[beecee]

4 hours ago, MigL said:

White holes only appear in 'maximally extended' solutions to the field equations.
That is, only where there are extended paths that particles can follow, without running into an 'edge' of space-time.

To me, they seem to be an artifact of observer frame dependency, and not a physical event.
And why would they be short-lived, in the order of hundreds of seconds; should they not last as long as BHs do since the event horizons are 'related' ?

I would more likely assume your GRB was related to the final 'evaporation' of a small, primordial BH, rather than a white hole, BeeCee.

What you say makes sense, particularly the query why they should be short lived. I was more or less playing the devil's advocate actually, as I did many moons ago, have a young GR expert explain to me why White Holes are impossible.

On 12/16/2017 at 9:17 PM, interested said:

Phase transitions took place during the big bang, is it likely these are reversed inside a black hole due to pressure and temperature?

Big difference being that the BB was the evolution of spacetime as we know it, while a BH occurs in spacetime.