Paradox Resolved in Scientific American of September 2022

This document contains comments about the article Paradox Resolved by George Musser In Scientific American of September 2022.
How competing teams of researchers made the first breakthroughs in one of the deepest mysteries in physics
To read this article select: https://www.scientificamerican.com/article/how-physicists-cracked-a-black-hole-paradox/

Reflection

"Introduction"

A few years ago a team of chemists unboiled an egg. Boiling causes protein molecules in the egg to twist around one another, and a centrifuge can disentangle them to restore the original.
What this means is that when you observe both, a raw egg, and a raw egg which is first hard boiled for 10 minutes and then unboiled, using a centrifuge, there is no physical difference. I have great doubts.
May be here is the answer?
https://www.washingtonpost.com/news/speaking-of-science/wp/2015/01/28/how-and-why-chemists-figured-out-how-to-unboil-an-egg/
The result is disappointing. Anyway you cannot unscramble, scrambled eggs.
The technique is of dubious utility in a kitchen, but it neatly demonstrates the reversibility of physics.
No you cannot If you want to boil water the process requires a heating element as a source of energy.
If you want to freeze water the process requires a cooling element to remove energy.
That means if you want both boiling and cooling you need both a heating and a cooling element and a switch, which has to be human manipulated in order to start the reverse action.
The switch is the most difficult part of the process, to take care that one comes after the other.
Anything in the physical world can run both ways—it's one of the deepest features of the laws of physics, reflecting elemental symmetries of space, time and causality.
All of that is not true. Each process will evolve only in one direction.
For example: the two processes (1) A+B -> C+D and (2) C+D -> A+B look identical, but they are not. Which one will be selected depents about the concentrations involved. This information should be part of the laws that describe each reaction. Both will evolve to a certain equilibrium condition and then stop. If (1) was selected and reaches equilibrium, the elements C and D have to be added to select (2).
For example: the movement of the planets around the Sun only go in one direction. This direction can not be reversed.
From a mathematical point of view, based on observations, you can predict the future. Using mathematics you can also predict the past.
However, the most difficult part is when there are collisions between two objects or when two objects merge into one. In that case there is what you can call "loss of information". This means when after this merging event, based on observations of this single objects it is not any more possible to predict that there was a merge and when this event took place. For example: Newton's Law is the law that can be used to predict the positions of the planets. The laws assume that gravity acts instantaneous. That means that the force of attracting of one object, at any instant in time, assuming only 2 objects, always exactly points towards the other object. That is wrong. That in turn means, that you cannot use Newton's Law to predict neither the future nor the past exactly.
If you send all the parts of a system into reverse, what was done will be undone.
It is physical impossible to perform this experiment in reality. To discuss such an IF experiment does not make sense.
Of course, undoing a process may be easy in simple systems but is less so in complex ones, which is why the egg unboiler was so nifty.
It makes only sense to discuss complex problems. But what ever the process is you need manual intervention, to modify or reverse the normal course of evolution.

But there's a troubling exception: black holes. If a massive enough star collapses under its own weight, its gravity intensifies without limit and locks matter in its grip.
More or less the same problem exists with all process where gravity is involved.
Raining, falling water, is a rather simple process. To take care that the same water droplets fall again, is a very complex process.
Looking at it, you can't tell what fell in.
When a small one merges with a large one this can still be observed. The assumption is that during the merging there is no mass loss, meaning the total mass will stay the same. In that case the trajectories of the other objects will not change.
The black hole does not seem to preserve information.
To understand the physics of a BH you don't need the concept of information.
See: Reflection 1 - What are the differences and the similarities between our Sun and the BH Sagitarrius A* in centre of our Galaxy
This irreversibility, first appreciated by physicist David Finkelstein in 1958, was the earliest inkling of the black hole information paradox—“paradox” because how could reversible laws have irreversible effects?
What is true that BH merging is an irreversible effect, but so are all processes when gravity is involved. As far as there is information loss, the details of what collided or merged with the BH is lost. Also the moment of merging is lost.
In the 1970s Stephen Hawking—in the work that made him a household name—took a first crack at including those effects. His calculations predicted that black holes slowly release energy.
This calculations should start with what is observed. My interpretation is that the amount released is very small.
But this emission carries no information about whatever had fallen in, so it doesn't help wind back the clock. If anything, the outgoing trickle of particles worsens the predicament.
No it does not, because we try to solve a problem, while there is no problem.
The key element in Page's and Mathur's analyses was quantum entanglement, a special kind of correlation that particles can have even when no force or other influence links them.
The physical situation is that when particles are entangled, they are created 'simultaneous' at one position. The degree of correlation disipates slowly.
Most particles that fall into one are entangled with particles that remain outside, and these linkages must be maintained if the black hole is to preserve information.
How do we know, assuming that a particle inside a BH, was correlated with a particle outside the BH, that this entanglement is maintained?
My understanding is that that is impossible.
Oddly, the storage capacity of space scales up with a region's area rather than with its volume. Space looks three-dimensional but acts as if it were two-dimensional. It has an illusory quality that we are usually oblivious to but that becomes evident in a black hole.
All of this text is very unclear.

That realization is the origin of what became known as the holographic principle, one of the most fascinating—and baffling—ideas in modern theoretical science.
All of the text in this paragraph is unclear.
Scientists have refined this duality over the years. Today not only can physicists equate a 3-D space to a 2-D space, they can match specific parts of the 3-D space to specific parts of the 2-D one.
Also this paragraph is unclear.
With all these ingredients in place, theorists were recently able to make a new assault on the black hole information paradox. In 2019 Almheiri, Engelhardt and their colleagues, and independently Geoff Penington of the University of California, Berkeley, were able to show how information could escape from black holes in the way Page had prescribed.
General speaking, information is not a physical concept. A Black hole could emit radiation.
In so doing the researchers confirmed that black holes are reversible after all.
This conclusion is too speculative.
Later the same year these and other authors, again working in two parallel teams, double-checked that the outgoing radiation bears the information that the black hole lets out.
Also this text should be based on actual observations. I expect it does not.

A black hole builds up such a gargantuan amount of entanglement that the geometry of spacetime undergoes a dramatic transition. Spacetime inside and around the black hole takes on convoluted shapes, including wormholes that resemble the spacetime portals of science fiction. These wormholes connect the interior of the black hole to the outside world, although how they enable information to escape is still unclear.
Specific the last part is very unsatisfying.
The use of wormholes is also very unscientific.
Bizarre though this geometric transition may sound, it fits perfectly well into existing physics.
This sounds as: there is no problem.
Whatever else you may say about black holes, they are no longer paradoxical—they don't represent an internal inconsistency within current theories.
IMO black holes were never paradoxical.

To a degree, the same can be said of most theoretical models, but this one makes idealizations that are not at all innocent, these authors say. For instance, it supposes that gravity not only weakens with distance but eventually shuts off altogether.
These type of discussions are very tricky.
That assumption fundamentally changes the nature of this force, so that the calculations, though technically correct, say little about gravity or black holes in the real world.
What is the meaning of a piece of text, when it is not relevant for the real world.
Mathur and others also argued that the new work implies a nonlocal effect—one that does not propagate through space but jumps from one place to another—to extract information from the black hole.
From a physical point of view, a strange explanation.
That in itself is not surprising. Physicists broadly agree that black holes require nonlocal effects to make sense.
Does not makes sense.
But the specific type of nonlocality in the new analyses strikes some skeptics as implausible.
The whole discussion is rather adhoc.
Both Raju and Mathur advocate alternative solutions to the information paradox. Raju suggested that information doesn't have to get out of a black hole, because it is already out.
What is the purpose of this empty sentence
Gravity has a long tail — the force acts over an unlimited range — that prevents information from ever being bottled up in the first place, he says. The gravitational, electromagnetic and other quantum fields outside the black hole retain an imprint of whatever falls in.
Also an empty sentence
“This region is rich in information,” Raju says. Mathur, for his part, argues that true black holes never actually form. As a star starts to collapse, it awakens the exotic physics of string theory, according to which all particles are vibration patterns in a more primitive type of matter. Stringy physics arrests the collapse, leaving a highly compact star, also known as a fuzzball. This little star does not wall itself off gravitationally, and information rides out on its light.
It is tricky to invent a new object as a replacement for a Black Hole

These ideas and their variants have critics, too. Indeed, Mathur and Raju disagree with each other's approaches. So the nature of black holes is still up for grabs. And continuing the historical trend, theorists are doing better at finding new puzzles than at solving old ones.

The physicists should clearly define what is agreed and what not.
In recent years Leonard Susskind of Stanford has noted yet another paradox of black holes. Space inside them is so stretchy that their interior volume should grow forever. Such expansion, however, would violate the principle that any closed system will reach equilibrium. Some heretofore unsuspected physics must eventually intervene to stabilize the interior.
What is the problem?

Susskind and others also find that black holes are frenetically chaotic systems, swirling and seething underneath their featureless façades. This aspect of black holes, at least, can be studied in computer simulations and laboratory experiments.

Which are the observations behind these computer simulations?
How can Blackholes be studied in computer simulations
Creating a real black hole is beyond them, but experimentalists are looking at the same chaotic dynamics in ions, condensates and other material systems.
That involves a risk.
They run the system, then unwind it; bringing it back to its exact starting point requires exquisite precision, demonstrating how black holes can look irreversible even if, in principle, they are rewindable.
As explained in
Meanwhile theorists think that what goes for black holes may go for the universe as a whole. Because our universe is expanding at an accelerating rate, it has a one-way surface much like that of a black hole's event horizon, and physicists hope that insights about black holes will offer up secrets of the cosmos as well. (Read more about this idea in Edgar Shaghoulian's article.)

Reflection 1 - What are the differences and the similarities between our Sun and the BH Sagitarrius A* in centre of our Galaxy.

There are three major differences.
  1. First of all the mass of Sagittarius A* is roughly 4 million times larger than the mass m0 of our Sun.
  2. Secondly comparing two objects with the same mass, the radius of a BH is much smaller than the radius of a star.
    The same can be set of the density: The density of a BH is much larger than the density of our Sun
  3. Thirdly a BH does not emit light. A star emits light. As such a BH can not be observed.
There are three major similarities or minor differences.
  1. The mass of a BH and a star are both baryonic.
  2. A BH of 4 million m0 can be described as the merging of 4 million suns, together with a mixing and a collapse. That means the internal constitution of two 4 million m0 BH's most probably is not the same.
  3. The internal processes within a BH and the Sun are physical processes.
  4. Both the Sun and a BH have a gravitational field i.e. emit gravitons. As such both can be detected.
    A BH can be detected by means of the stars which revolve around the BH.
What is not mentioned is the word information. This is done on purpose.
The merging of two objects can be described with 3 scenarios:
  1. When a star merges with a BH the mass of the BH increases with 1 m0. At the same time the rich structure of the star disappears and becomes part of the more uniform structure of the BH.
  2. A different scenario can be that two BH's first collide with each other resulting in a cloud of planet sized objects. These objects can each slowly merge with the BH. This scenario takes much more time than scenario #1.
  3. The same scenario as #1 can also be used to describe the merging of our Sun with a comet.
When you compare scenario #1, #2 and #3 than they all are irreversible physical processes.

Reflection 2 - How reversible are chemical reactions.

An important chemical reaction between hydrochloric acid and sodium hydroxide, producing salt and water (1 molecule each) is:
HCl + NaOH → NaCl + H2O. (1)
There exist also the follow reaction:
NaCl + H2O → HCl + NaOH. (2)
This is the same reaction as (1), but in the opposite direction
The reaction is performed by adding a certain amount of HCl with NaOH. The result is a mixture of HCL, NaOH, NaCL H2O.
To answer the question How reversible are chemical reactions in case of HCL, NaOH, NaCL, and H20? The answer in Yes. This reaction can go in two directions, under the assumption that at every position inside the reactor, at every point in time, only one of these two reactions can take place. That means each reaction always takes place in a certain region.
In case of water boiling and water cooling? The answer is No. In case of water boiling additional equipment is required to heat the water and the same for water cooling. This extra special equipment is part of the process and the result is that they are not reversible.
In the case of the planets around the Sun? The answer is also NO. You cannot stop the planets and start the planets instantaneous and at the same instant reverse their directions.

Reflection 3 - General Reflection.

The central theme of this article is the "information paradox". The physical issue in this article is: that the merging process which involves a BH and a large object, can not be reversed. This means that such a process is ireversible. This means there is no way to bring the two original objects back to 'live'. A similar problem with the extinction of the dinosaur. Once extinct always extinct.
In the article the merging of a BH and any other object is considered information loss and a paradox because this is the only case of all the processes in the universe that have characteristic. IMO that is not the case. All processes which involve gravity have this.
The second step is to solve this paradox. The problem is that everything what is discussed is not clear. Concepts discussed like the holographic principle, 2D space, quantum entanglement, worm holes, string theorie and fuzzball are not clear. At the end the paradox is considered solved, but the whole discussion has a bad taste, also because not everyone agrees.

IMO opinion the merging of BH's is a fact of live and there is no information paradox.
A much more important question is if two isolated BH's, revolving around each other, will always merge or when this happens always an other large object, a third BH is involved? IMO that will be the case. This third object will influence the elliptical trajectories of original binary system such that a collision becomes much more probablistic.

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Created: 22 August 2022

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