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Dark energy


Jon O'Starr

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About myself

 

I have just joined this forum and wish to describe my background.

Educated to M.Sc. Level, with some relevant work experience thereafter, I opted for a more mundane career some 40 years ago and have been a carpenter and joiner ever since. I have always retained an interest in many fields of science – this in no participatory manner, more by way of reading “popular science” and relevant TV viewing.

 

 

Dark energy

 

So, this is an idea that occurred to me, I would not wish to present it as a theory, more as an idea for discussion. I would be totally not surprised to find that it is not original and can be discounted for (many) theoretical and observational reasons.

 

Assume black holes attract more matter then contributes to their increase in mass, and that this surplus mass is transformed into energy. As electromagnetic energy it could not be emitted by the black hole, but as quantum entities could it tunnel out? If it did this, why has no one detected it?

Maybe its not electromagnetic and we do not currently have the means for its detection.

Maybe it appears as randomly spread, “photon sized” white holes and the energy is dissipated in the creation of the space needed for said white hole.

(Most heretically, maybe we did but misinterpreted it as CMB.)

Dark energy sums.doc

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18 minutes ago, Jon O'Starr said:

Assume black holes attract more matter then contributes to their increase in mass, and that this surplus mass is transformed into energy.

Welcome to the forum.  You are supposed to present your ideas here so we don't have to open files outside the site.

How would the matter be transformed into energy?

21 minutes ago, Jon O'Starr said:

As electromagnetic energy it could not be emitted by the black hole, but as quantum entities could it tunnel out?

What do you mean by a quantum entity?  Isn't a photon a quantum entity?

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I wasn't expecting such quick responses, thanks.

I cannot answer how the matter might be transformed, who knows what goes on and what is possible inside a black hole. Hence speculation.

Yes, I do recognise a photon as a quantum entity, and as such I was asking if it might 'tunnel' out.

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2 hours ago, Jon O'Starr said:

Assume black holes attract more matter then contributes to their increase in mass, and that this surplus mass is transformed into energy. As electromagnetic energy it could not be emitted by the black hole, but as quantum entities could it tunnel out? If it did this, why has no one detected it?

Maybe its not electromagnetic and we do not currently have the means for its detection.

Maybe it appears as randomly spread, “photon sized” white holes and the energy is dissipated in the creation of the space needed for said white hole.

(Most heretically, maybe we did but misinterpreted it as CMB.)

When it comes to experiments on black holes, it gets a bit tricky. You cannot produce them in the lab, and none of these things exists naturally on earth. In fact, we had put lots of efforts into even detecting anything in the universe that we concluded/agreed must be a black hole. While double-checking if even that has happened, yet, I ran into an article claiming that 2019 was the first time you could get an image of a black hole (https://www.sciencemag.org/news/2019/04/black-hole). Don't pin me on the accuracy of that statement, but my point is: It is already pretty challenging to detect black holes in the first place, so you cannot expect these objects to be as well researched experimentally as, e.g., a laser diode.

 

I don't think there is any accepted idea how something could evade the event horizon of a black hole. I am not sure if even tunneling would work, but that is certainly an interesting mathematical question. Today, I think the idea of Hawking radiation is a widely accepted mechanism of how black holes emit energy (in addition to the normal jet emissions). I've never bothered to read up on in, but popular scientific depictions of it describe it as an effect happening outside of the event horizon.

 

As for white holes: Formally, they appear if you allow the distance-to-center coordinate to become negative, which creates a second volume of spacetime with similar properties as the original one, except that nothing can enter the event horizon (whereas before nothing could exit from there). You can fantasize about this being a white hole, the exit of a black hole. And you can fantasize about making this passable, which is then called a worm hole. Usually, you'd have exactly one white hole exit for a black hole. But well, maybe something interesting happens if you make the radius coordinate a complex value. I don't quite see how that would relate to the CMB. Also, keep in mind that the CMB is pretty well understood and, in contrast to black holes, experimentally measured with an extreme precision (https://en.wikipedia.org/wiki/Cosmic_microwave_background#/media/File:Cmbr.svg) - with the caveat that it is only measured within a single solar system.

Edited by timo
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While tunneling has been postulated as a mechanism for Hawking Radiation ( along with some other mechanisms ), 
see here         [hep-th/9907001] Hawking Radiation as Tunneling (arxiv.org)

Hawking radiation will only come into play once a Black Hole is small enough that its 'temperature' exceeds the CMB temperature of 2.7o, otherwise the BH is an absorber of radiation, making it grow ( and get 'colder' ).

As for 'White" Holes, you would think the 'tell tale' radiation from such an object would be readily detectable.
And while GR may allow for their existence, it is not a guarantee of such, and none have ever been detected.

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3 minutes ago, MigL said:

While tunneling has been postulated as a mechanism for Hawking Radiation ( along with some other mechanisms ), 
see here         [hep-th/9907001] Hawking Radiation as Tunneling (arxiv.org)

Hawking radiation will only come into play once a Black Hole is small enough that its 'temperature' exceeds the CMB temperature of 2.7o, otherwise the BH is an absorber of radiation, making it grow ( and get 'colder' ).

As for 'White" Holes, you would think the 'tell tale' radiation from such an object would be readily detectable.
And while GR may allow for their existence, it is not a guarantee of such, and none have ever been detected.

Imagine that... 😁

Cybermen are allergic to gold, right?

 

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Nothing but nothing can get out of a BH. By definition, a BH forms when the surface of a gravitationally collapsed mass, reaches the escape velocity of the universal speed limit, of "c", or the speed of light. Once this is reached an EH forms, which coincides with what is known as a mass's Schwarzchild radius. Once this radius is reached, GR tells us that further collapse is compulsory, up to at least the quantum/Planck level where GR fails us.

As the mass collapses to this level, it is ripped asunder by the tidal gravitational effects to its most basic fundamental components. Once the quantum/Planck level is reached, GR fails us and we are only able to guess. Most scientists and cosmologists though as far as I know, reject a collapse to a singularity as defined by infinite spacetime curvature and density, which then speculatively assumes a surface of sorts at or just below the quantum/Planck level. 

Or we can speculatively accept a wormhole and ERB to  an outpouring and White Hole. NOTE: While White Holes and wormholes are allowed  for by GR, we have absolutely no observational evidence for their existence.

Hawking Radiation is a prediction based on the scenario that if virtual particle pairs happen to pop into existence just outside the EH, one of three things can happen...[1] Both escape and annihilate...[2] Both immediately fall into the BH, or [3] One escapes and becomes real and which we see as thermal radiation, the other falls into the BH and because of the law of conservation, becomes negative, which subtracts ever so slightly from the overall mass of the BH.

The CMBR is of course evident everywhere we look at 2.73K and is logically assumed to be the left over relic heat from the BB.

 

We don't know what DE is but it is assumed to be responsible for the observed acceleration in the expansion rate of the universe, or a property of space itself.

Edited by beecee
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1 hour ago, beecee said:

Nothing but nothing can get out of a BH. By definition, a BH forms when the surface of a gravitationally collapsed mass, reaches the escape velocity of the universal speed limit, of "c", or the speed of light. Once this is reached an EH forms, which coincides with what is known as a mass's Schwarzchild radius. Once this radius is reached, GR tells us that further collapse is compulsory, up to at least the quantum/Planck level where GR fails us.

As the mass collapses to this level, it is ripped asunder by the tidal gravitational effects to its most basic fundamental components. Once the quantum/Planck level is reached, GR fails us and we are only able to guess. Most scientists and cosmologists though as far as I know, reject a collapse to a singularity as defined by infinite spacetime curvature and density, which then speculatively assumes a surface of sorts at or just below the quantum/Planck level. 

Or we can speculatively accept a wormhole and ERB to  an outpouring and White Hole. NOTE: While White Holes and wormholes are allowed  for by GR, we have absolutely no observational evidence for their existence.

Hawking Radiation is a prediction based on the scenario that if virtual particle pairs happen to pop into existence just outside the EH, one of three things can happen...[1] Both escape and annihilate...[2] Both immediately fall into the BH, or [3] One escapes and becomes real and which we see as thermal radiation, the other falls into the BH and because of the law of conservation, becomes negative, which subtracts ever so slightly from the overall mass of the BH.

The CMBR is of course evident everywhere we look at 2.73K and is logically assumed to be the left over relic heat from the BB.

 

We don't know what DE is but it is assumed to be responsible for the observed acceleration in the expansion rate of the universe, or a property of space itself.

I came across the following note on the Internet. "Physicists Laura Mersini-Houghton and Harald Pfeiffer  suggested
that black holes do not exist. The Englishwoman and the Canadian presented the results of their research in two preprints available on the resource arXiv.org.
A brief summary of the work can be found on the website of the University of North Carolina at Chapel Hill (USA).
Scientists have tried to show by theoretical and computer calculations that the evolution of massive objects will not reach the stage of black hole formation.
According to their hypothesis, a dying heavy star will lose mass along with the radiation, which will not allow it to shrink to form a black hole.
The completion of the evolution of the star, in the view of the authors, will end with its expansion and explosion. (End of quote with https://texnomaniya.ru/uchenie-usomnilis-v-sushestvovanii-chernih-dir)

I tried to solve a simple problem, to calculate to what radius it is necessary to compress the Sun so that it turns into a black hole, but taking into account the mass defect
associated with an increase in the gravitational binding energy during compression. After the compression, the mass of the sun will be

defmass.jpg

next, we substitute M, taking into account U, in the equation for the Schwarzschild radius, where U is the gravitational binding energy, for the ball it is calculated by the formula

le.jpg

next, we substitute M, taking into account U, in the equation for the Schwarzschild radius

rsh.jpg

The resulting equation is converted to a square equation with respect to R

sqeq.jpg

Its discriminant is equal to

deq.jpg

Wow! The discriminant is less than zero, the equation has no solution, the star cannot collapse into a black hole.
It may be objected to me that if we are talking about a black hole, then we cannot use Newton's theory, but we must use GRT.
The answer is that the Schwarzschild radius is calculated from Newton's theory, if you equate the speed of light to the second cosmic speed.

 

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40 minutes ago, SergUpstart said:

I came across the following note on the Internet. "Physicists Laura Mersini-Houghton and Harald Pfeiffer  suggested
that black holes do not exist.

I certainly remember Professor Mersini-Houghton's controversial paper when it was released in around 2014, and before the first discovery of gravitational waves, that aligned with that of BH's colliding/merging. I havn't heard much of her since.

And of course we also have many papers of other models of gravity, parallel universes [another of her predictions] and other versions of cosmology. That's science. But the facts remain, that the present model of cosmology, including the evidence for BH's, is that which is overwhelmingly accepted by the science community. I also recall an otherwise great astronomer that pushed "Steady State" rather then accept the evidence for the BB as currently recognised. And certainly, while cosmology in general still has some problems, the current model that entails the BB/GR, still fits our observational data better then anything else.

As an amateur, and ignoring the convincing evidence of gravitational waves and the BH templates they fit, I would ask anyone questioning the existence of BH's, to explain to me the observational data of spacetime, the orbital velocities of stars, and other phenomena around what we propose as BH's, in another way. 

1 hour ago, SergUpstart said:

It may be objected to me that if we are talking about a black hole, then we cannot use Newton's theory, but we must use GRT.
The answer is that the Schwarzschild radius is calculated from Newton's theory, if you equate the speed of light to the second cosmic speed.

Newtonian theory predicts what we could call "Dark Stars" first hypothesised by John Michell in the 1700's. It did not though predict the continuing compulsory collapse at the Schwarzchild limit which GR does. Not sure what you mean by the "second cosmic speed"

 

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5 hours ago, SergUpstart said:

According to their hypothesis, a dying heavy star will lose mass along with the radiation, which will not allow it to shrink to form a black hole.

Makes you wonder how 4.1 million solar masses could be concentrated within a radius equivalent to the orbit of Uranus, in the region Sagittarius A, of our galaxy. From    https://en.wikipedia.org/wiki/Supermassive_black_hole

"The star S2 follows an elliptical orbit with a period of 15.2 years and a pericenter (closest distance) of 17 light-hours (1.8×1013 m or 120 AU) from the center of the central object.
From the motion of star S2, the object's mass can be estimated as 4.1 million M,[73][74] or about 8.2×1036 kg.
The radius of the central object must be less than 17 light-hours, because otherwise S2 would collide with it. Observations of the star S14[75] indicate that the radius is no more than 6.25 light-hours, about the diameter of Uranus' orbit.
No known astronomical object other than a black hole can contain 4.1 million M in this volume of space."

Or how they could possibly take a picture of one

https://www.space.com/first-black-hole-photo-by-event-horizon-telescope.html
 

10 hours ago, dimreepr said:

Imagine that... 
Cybermen are allergic to gold, right?

I need a Dimreepr to Human dictionary.

Edited by MigL
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40 minutes ago, MigL said:

Or how they could possibly take a picture of one

https://www.space.com/first-black-hole-photo-by-event-horizon-telescope.html

Bingo!!! I missed probably the most important extraordinary evidence of BH's. Off with my head, on goes a pumpkin!!

Thanks MigL

Like I said earlier, Professor Laura Mersini-Houghton has been rather quiet of late.

Edited by beecee
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9 hours ago, SergUpstart said:

The answer is that the Schwarzschild radius is calculated from Newton's theory, if you equate the speed of light to the second cosmic speed.

The Schwarzschild solution is static and stationary, and it requires some boundary conditions that one wouldn’t find in the real world for this type of event - so it is not a suitable model to describe the actual collapse process itself. It can only be used to approximately model either the end result or the original gravitating object, i.e. the original star or the resulting black hole, which are then assumed to be static and unchanging. Describing the collapse process itself is a very much more complex task, which can really only be done using numerical methods.

The reason why the event horizon radius in Schwarzschild spacetime happens to agree with a suitable Newtonian calculation is that this type of spacetime is spherically symmetric and asymptotically flat. But this is not necessarily true in general - if you relax any of the boundary conditions of Schwarzschild (e.g. allow the central mass to carry angular momentum, or electric charge), the location of the event horizon will no longer agree with Newtonian theory. In fact, you will quickly find that there is in fact more than one horizon surface, giving quite a complex structure. The existence, nature, and location of horizon surfaces is intrinsically a relativistic phenomenon which has to do with the causal structure of the spacetime in question.

10 hours ago, SergUpstart said:

Wow! The discriminant is less than zero, the equation has no solution, the star cannot collapse into a black hole.

It can, and (given certain conditions) inevitably must - but you have to use the correct model.

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1 hour ago, Markus Hanke said:

The reason why the event horizon radius in Schwarzschild spacetime happens to agree with a suitable Newtonian calculation is that this type of spacetime is spherically symmetric and asymptotically flat.

I think the reason here is simple: the light beam is deflected by gravity at an angle twice as large as the moving macrobody. Therefore, in the solution for the radius of the event horizon, it is the second cosmic velocity that appears, and not the first.

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