Cosmology - Escape from a Black Hole in Scientific American of December 2019

This document contains comments about the article Escape from a Black Hole by Steven B.Giddings In Scientific American of December 2019.
To save quantum mechanics information must break free from black holes. New observations may help tell us how
To read this article select: https://www.scientificamerican.com/article/escape-from-a-black-hole/

Reflection

"Introduction"

This was a breathtaking achievement—our first view of one of the most mysterious objects in the universe, long predicted but never directly “seen.”
A Black hole can never directly be seen. It can only indirectly be induced by stars and small BH's in its direct surroundings.
This enigma is the “paradox” of what happens to information in a black hole.
A "paradox" is some sort of 2 conflicting explanations. Both explanations should be clear. 1 should be eliminated.
By investigating this question, physicists have discovered that the mere existence of black holes is inconsistent with the quantum-mechanical laws that so far describe everything else in our universe.
Which are all these laws? The mere existence of black holes can never be in conflict which everything else that exists in the universe. Most probably some of these laws are not clear.

THE INFORMATION PROBLEM

page 44

The EHT observations and the gravitational-wave measurements are just the latest and most robust evidence that black holes, despite sounding fantastical, do indeed appear to be real—and remarkably common.
Okay.
The basic principles of quantum mechanics are thought to govern all the other laws of nature, but when they are applied to black holes they lead to a contradiction, exposing a flaw in the current form of these laws.
This sentence should be changed into:
The basic processes at elementary particle level, the descriptions there of, should also be applicable for black holes.
The problem arises from one of the simplest questions we can ask about black holes: What happens to stuff that falls into them?
The same as for any merging of two objects.
First, according to our present quantum-mechanical laws, matter and energy can shift between different forms: particles can, for example, change into different kinds of particles.
It should be mentioned that all laws are descriptions of certain processes, they are not the cause of what happens when two objects collide or merge.
But the one thing that is sacred and never destroyed is quantum information.
Information has nothing to do with the merging of two objects.
What should be expected is that the energy conservation laws should be followed.
If we know the complete quantum description of a system, we should always be able to exactly determine its earlier or later quantum description with no loss of information.
To know the complete description at elementary particle level, before and after a merging is impossible and unrealistic.
So a more precise question is, What happens to quantum information that falls into a black hole?
Silence.
Our understanding of black holes comes from Albert Einstein’s general theory of relativity, which describes gravity as arising from the curvature of space and time; a common visualization of this idea is a heavy ball deforming the surface of a trampoline.
The problem if this visualization is correct, because this so called deformation happens all around the Black Hole.
This warping of spacetime causes the trajectories of massive bodies and light to bend, and we call that gravity.
Spacetime is a mathematical concept and cannot be the explanation why objects fall or follow a bended path, like commets around the Sun, or light (the path of photons) around a star is bended.
To call that: gravity is 'strange'. The logic of the sentence should be the other way around.
If mass is sufficiently concentrated in a small-enough vicinity, the nearby spacetime deformation is so strong that light itself cannot escape a region inside what we call the event horizon: we have a black hole.
The escape velocity of any particle can easily(?) be calculated as a function of mass and radius of an (round) object. When the velocity is larger than the speed of light the particle cannot escape. This means, that the object is not vissible. The radius of the sphere, with the escape speed of c, is called the event horizon.
Spacetime does not exist, it is a mathematical concept.
And if nothing can travel faster than light—including information—everything must get stuck inside this boundary.
Information has nothing to do with this, except if information is considered the modulation of a light signaal. Like morse signals. See Also: Reflection 2 - The definition of Information
Black holes become cosmic sinkholes trapping information along with light and matter.
Black holes are from a physical point of view almost identical as our Sun, except that they are much larger than our Sun and don't emit light.
Typically such a pair, consisting of a particle and its antimatter counterpart, quickly annihilates itself, but if it forms near the horizon of a black hole, one particle might pop up inside this boundary and the other outside.
The question is how often this wil happen and how sharp this boundary is.
The outside particle can escape, carrying away energy.
Okay.
The law of energy conservation tells us that the black hole has thus lost energy, so the emission of such particles causes the black hole to shrink over time until it completely disappears.
The problem is how important this specific outflow is. If one star collides with the Black Hole, this inflow can erase completely this outflow and the overall Black Hole will grow. This seems in agreement of what is observed.

page 45

The Information Problem.

In 1974 Stephan Hawking argued that Black Holes eventually evaporate.
In principle there is nothing wrong with this claim.
What is important are the physical details of what evaportes.
The only type of evaporation is the emission of gravitons, these are the bearers of the information in the form of gravitational waves, which we can detect to induce the existance of for example two BH's.
If so, everything that falls into them is destroyed, including the information (1) contained in the matter that fell in.
In formation is not a separate 'item'. Information is an integral part of the description of objects that are 'destroyed'.
But that is not true. The total mass and the strength of the gravitational field increased
The problem is that quantum mechanics and energy conservation forbids such destruction of information.
There is nothing to indicate that during the merging or collision between a Black hole and any object the energy conservation law is violated
Most probably there is information loss around the details at elementary particle level at both sides of the collision or inside the BH. But that is part of the game. At the LHC the same thing happens with each experiment or collision.
In response physicists have come up with several suggestions to how to modify our picture of black holes to make them compatible with quantum physics.
There is no reason for these suggestions, because there is no paradox
The problem is that the escaping particles, known as Hawking radiation, carry essentially no information about what went into the black hole.
Why is it a problem that there apparantly exists no relation between what goes in, versus what goes out?
For our star what goes in are commets, what comes out is radiation in the form of light and gravitons.
For a Black Hole all what goes out are gravitons.
Therefore, Hawking’s calculations appear to show that quantum information that falls into a black hole is ultimately destroyed—contradicting quantum mechanics.
The word appear is important, because it idendicates doubt.
The question is what does quantum mechanics exactly claims about (quantum) information.
A different question is, what are the calculations Hawking performed and to what extend they are validated by observations.
This revelation initiated a deep crisis in physics.
What is required is a clear and detailed description of what is physical happening.
One process is that the Black Hole almost continuous absords matter. That is how the BH grows.
A second process is radiation emitted by the BH. The details of this process are missing.
For instance, at the beginning of the 20th century, classical physics seemed to predict the inevitable instability of atoms, in obvious contradiction to the existence of stable matter.
With hinsight such a prediction does not seem very clever.
Increasingly it seems that the black hole crisis will similarly lead to another paradigm shift in physics.
This will only happen if there exists a clear physical issue.

QUANTUM ALTERNATIVES

When Hawking first predicted black hole evaporation, he suggested that quantum mechanics must be wrong and that information destruction is allowed.
The question is: What does information destruction mean
During any collision between two objects, you can speak of information destruction, in the sense that there is information loss within the context of the detailed description of the two objects that collided. Both objects can be damaged or one object can completely disappear. This does not mean that the energy conservation law is violated.
Yet physicists soon realized this change would require a drastic breakdown of the law of energy conservation, which would disastrously invalidate our present description of the universe.
More detail is required of this sentence. Specific about the second half.
Another early idea was that black holes do not completely evaporate but instead stop shrinking at a tiny size, leaving behind microscopic remnants containing the original information.
It should be emphasized that the concept of evaporation is speculative and can not demonstrated by any experiment. The reverse that Black Holes can grow in size, makes much more sense. The same can also be 'observed' by the planets around the Sun.
But, scientists realized, if this were true, basic properties of quantum physics would predict catastrophic instabilities causing ordinary matter to explode into such remnants, also contradicting everyday experience.
Why proposing first something that is highly unlikely and than claiming that it will not happen, because the consequences i.e. explosions, are not observed.
It is tempting to conclude that the flaw is in Hawking’s original analysis and that somehow information does escape a black hole emitting Hawking radiation.
The most important physical fact is that accordingly to Stephen Hawking a Black Hole emits radiation. In principle there is nothing wrong with this prediction. However this has nothing to do with some sort of information paradox.
The problem is that this is in some sense in conflict with the fact that this object is invisible, because it does not emit light.
At the same time the BH emits gravitation, which is demonstrated by the large stars which are circulating around the BH Sagitarrius A* in the center of our Galaxy, the Milky Way.

For the interesting reader select this link: https://en.wikipedia.org/wiki/Astrophysical_jet It gives an impression that a Black Hole can emit ionised matter. At least much more than this article seems to indicate.
The same information comes from an article in Nature of 24 November 2022: "In the early 1960s etc. The relevation that these black holes could launch such energetic jets from their cores came in the decades that followed, as radio astronomy advanced and the first satellites dedicated to observing emissions in X-ray and gamma-ray frequencies were launched. These jets can be thought of as cones, in which charged particles are accelerated close to the speed of light, and release huge amounts of energy in the form of radiation. "

The challenge here is that this scenario would conflict with a foundational concept of present-day physics, the principle of locality, which states that information cannot move from one place to another superluminally—that is, faster than the speed of light.
My understanding is that nothing can move faster than the speed of light.
Light is a form of radiation. The question is if all forms of radiation (along the whole frequency spectrum) have the same speed.
But according to our definition of black holes, the only way to escape one is to travel faster than light, so if information does escape, it must be doing so superluminally, in conflict with locality.
Also this sentence requires a confirmation that actual something escapes from, or is emitted by a BH.
If it does not, the sentence does not make sense.
If it does as explained in the Nature article, the concepts superluminally and locality are not required.
In the four decades since Hawking’s discovery, physicists have tried to find a loophole to this argument that stays within conventional physics, but none has emerged.
Hawking has not discovered anything (in this context!), he has predicted something. The only thing, that is important, what is observed.

page 46

The closest attempt was a 2016 proposal by Hawking, Malcolm Perry and Andrew Strominger, who suggested that a mistake in the original analysis implies information never fully enters a black hole and instead leaves a kind of imprint in the form of what they called "soft hair" outside it.
This is a wrong approach.
In reality objects can increase and decrease in size.
To invent something like "soft hair", requires a detailed description.
It is tricky to expain something that is not clear by creating a new concept that is also not clear.
Closer examination seems to be closing this loophole, however, and most experts do not believe this can be the answer. In short, more radical steps appear to be needed.
All this makes sense, but the overall remark is that physics
An obvious idea is that there is some unknown physics that prevents true black holes from existing at all.
This sentence falls in the cathegory of circular logic. See Reflection 1 - Proper science
When black holes don't exist, you do not need 'unknown physics'
Perhaps some unknown laws of physics also prevent larger stars from forming black holes and instead lead them to become a kind of “massive remnant”—something more like a neutron star than a black hole.
What this sentence claims is larger stars, during their evolution, directly could become neutron stars.
Such a claim should be supported, by what is observed.

page 47

A related idea is that something could cause black holes to change into massive remnants containing the original information after they form but long before they evaporate.
It should be remembered that the most obvious reason that blacks holes can change into massive remnants is when two black holes collide, influenced by a third black hole.
But once again, this story requires nonlocal transfer of information from the interior of the initial black hole to the final remnant.
It should be remembered that two Black Holes of equal size are rather stable. A third Black Hole drastically changes this picture.
Information transfer is not involved.
For example, in 2003 Samir Mathur put forward a proposal based on string theory, which posits that fundamental particles are tiny strings.
That is possible, but it is not enough to understand how black holes are created and die.
His idea is that a black hole transforms into a "fuzzball", a kind of massive remnant, or that a fuzzball forms instead of a black hole in the first place.
The introduction of a "fuzzball" is not convincing.
Thanks to the complicated physics of string theory and its allowance for more than the traditional four dimensions of spacetime, fuzzballs might have a complex higher-dimensional geometry; instead of the sharp traditional boundary of a black hole at the event horizon, a fuzzball would have a fuzzier and larger boundary where one encounters strings and higher-dimensional geometry.
All of this is not clear.
Alternatively a more recent version of a remnant scenario is the proposal that instead of a black hole with an event horizon, a massive remnant forms with a surface "firewall" of high-energy particles where the horizon would be.
A concept firewall is not clear.

MODIFYING LOCALITY

A common thread in massive-remnant proposals is that saving quantum mechanics appears to require violation of the locality principle.
It should be remembered that the massive-remnant proposal is speculative and not supported by clear observations. The only exception is when 3 massive objects are involved, which can collide.
Specifically, the laws of relativity say that if you send a faster-than-light signal in empty, flat space, observers traveling past you at a high-enough speed will see the signal going backward in time.
SR should be based on actual experiments. As such an actual should demonstrate that some something moves faster than light. For example: the simultaneous emission of a photon and a neutron, in the same direction at point A, and the measurement of the two events that each arrives at a point B. The prediction is that the photon arrives first.
A lighthouse emmits light in two opposite direction. Each of the two packages in opposite directions have a speed c. The relative speed is 2*c. That does not mean that anything moves backward in time, nor that anything
The paradox arises because this superluminal signaling then allows you to send a message into your past, for example, asking someone to kill your grandmother before your mother is born.
As already mentioned it is not possible that any lightsignal, moving towards the right is surpassed by a lightsignal also moving towards the right.
The fact that a moving clock B runs slower than a clock A at rest is no idication that time runs slower. It means that you should use only clocks at rest.
Put differently, quantum mechanics implies information is never destroyed, so information that falls into a black hole must ultimately escape, possibly through some new, subtle “delocalization” of information that might become clear when we can finally find a way to unify quantum mechanics and gravity—one of the most profound problems of present-day physics.
It is important to study: Reflection 2 - The definition of Information. What this emphasizes that in effect there is a clear distinction between information and matter.
The very idea of localized information—that it can exist in one place and not in another—is more delicate in theories that include gravity than in those that do not, because gravitational fields extend to infinity, complicating the concept of localization.
What this sentence emphasizes is that there is a clear distinction between matter and information. Matter is a condition of all objects in the universe. Matter creates a gravitational field and under certain circumstances gravitational waves. Information is something relevent for a specific object or blackhole.

page 48

In my theoretical work, I have found two versions of such effects.
A certain type of phylosophical discussion is required to explain what is meant with theoretical work. Specific the relation with actual experiments should be discussed, which services as a certain way of validation.
In this “strong, nonviolent” scenario, such shimmering of spacetime can transfer the information out.
How realistic is this?
In this “weak, nonviolent” scenario, even tiny quantum fluctuations of the spacetime geometry near the black hole can transfer information to particles emanating from the hole.
How realistic is this?
In either picture, a black hole effectively has a “quantum halo” surrounding it, where interactions pass information back to its surroundings.
The only way that this scenario is realistic is when gravitational waves are considered. The problem is: I expect that the quantities involved are minor.
Notably, these scenarios, despite appearing to require superluminal travel of information, do not necessarily produce a grandmother paradox.
This sententence has a high level of circular reasoning.
The issue is matter and not information.
These waves carry valuable information with them about the properties and behavior of the objects that created them.
The gravitational waves carry 'energy' about the mass of two objects involved. Not at elementary particle level.

REWRITING THE LAWS OF PHYSICS

So far such a quantum-halo scenario has not been predicted by a more complete theory of physics that reconciles quantum mechanics with gravity, but it is strongly indicated by the need to resolve the problem and by assumptions based on what we see.
Every physical process which evolves in time can be subdivid in smaller process. The inner workings of these processes is guided by cause and effect. As such the inner
The present work to understand black holes may be akin to the first attempts to model the physics of the atom by Bohr and others.
Comparing both does not make much sense, based on size.
Those early atomic descriptions were also approximate and only later led to the profound theoretical structure of quantum mechanics.
To make modifications to the Bohr model is 'complicated', because all reasoning has to be considered.

page 49

Reflection 1 - Proper science

Proper science starts by the accepting the rule that all concepts used should be clear.
Typical words used, which require clarification, are the concepts: Information, Quantum Mechanics , GR, SR, spacetime, sinkhole, locality, soft hair, strings, fuzzball, firewall, delocalization A second rule or step is the importance of experiments and observations.
A typical case is in point is to perform observations which cannot be explained or which are in conflict with other observations. In that case there is a chance that the explanation is not clear or the description of the conflict is not clear.
The third step is to describe the whole process in rather simple language.
One problem of this step is that existing laws are used to explain a certain physical process. A better approach is first to explain the process (almost) without any reference to any existing law and secondly to discuss the relation with these existing laws. A typical case is to find an answer on the question: Why does an airplane fly. See: The enigma of aerodynamic lift Often there can be a problem with what I would call: circular sentences or circular reasoning. A typical case is a sentence like: "The free will does not exist". The problem is if something does not exist, you can not explain what that 'something' is.
The sentence: "The free will does not exist" also causes a paradox. In order to explain what the sentence means we must first explain clearly what "A free will" is. To do that we should first agree that humans have the capability to have their own opinions and to make their own decisions and secondly that actual people have this capability. If that is the case you cannot claim that "the free will does not exist".

Reflection 2 - The definition of Information

In this document the concept Information is often used. What does it mean?
All what we know about a certain person, its name etc is information. All text in a book is information. The head and the tail of a coin, showing the value, also is information.
At position (1) information destruction is discussed. The problem is that during any merging or collision matter is desctructed, including detailed information about what is destructed. These two 'parts of a coin', the matter issue and the information issue, cannot be handled seperate .
These two unseperable parts, matter and information have both to be considered, when the energy conservation law is discussed.
The overall lesson is that the whole article should be rewritten without the word information. The result will be an overall improvement of the clearity of the article.

Reflection 3 - Information - The laws of physics

The laws of physics are also what is called: information. Laws are descriptions, by humans, of the evolution of identical physical processes. They should be supported by experiments and observations.

Reflection 4 - Information - Mathematics

Mathematics is the science which uses mathematical equations. Mathematics also belongs to information. Equations are mathematical descriptions, by humans, of the evolution of physical processes.
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Created: 22 November 2022

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