What Exactly is a Black Hole?
What is a black hole? In an article that has just appeared in the journal Nature Astronomy, LMU philosopher Erik Curiel shows that physicists use different definitions of the concept, depending on their own particular fields of interest.
A black hole is conventionally thought of as an astronomical object that irrevocably consumes all matter and radiation which comes within its sphere of influence. Physically, a black hole is defined by the presence of a singularity, i.e., a region of space, bounded by an ‘event horizon‘, within which the mass/energy density becomes infinite, and the normally well-behaved laws of physics no longer apply.
However, as an article in the January issue of the journal Nature Astronomy demonstrates, a precise and agreed definition of this ‘singular’ state proves to be frustratingly elusive. Its author, Dr. Erik Curiel of the Munich Center for Mathematical Philosophy at LMU, summarizes the problem as follows:
“The properties of black holes are the subject of investigations in a range of subdisciplines of physics – in optical physics, in quantum physics and of course in astrophysics. But each of these specialties approaches the problem with its own specific set of theoretical concepts.”
Erik Curiel studied philosophy as well as theoretical physics at Harvard University and the University of Chicago, and the primary aim of his current DFG-funded research project is to develop a precise philosophical description of certain puzzling aspects of modern physics.
“Phenomena such as black holes belong to a realm that is inaccessible to observation and experiment. Work based on the assumption that black holes exist therefore involves a level of speculation that is unusual even for the field of theoretical physics.”
However, this difficulty is what makes the physical approach to the nature of black holes so interesting from the philosophical point of view.
“The physical perspective on black holes is itself inextricably bound up with philosophical issues relating to ontological, metaphysical and methodological considerations,” says Curiel.
“Surprising” and “eye-opening” insights
During the preparation of his philosophical analysis of the concept of black holes for Nature Astronomy, the author spoke to physicists involved in a wide range of research fields. In the course of these conversations, he was given quite different definitions of a black hole.
Importantly, however, each was used in a self-consistent way within the bounds of the specialist discipline concerned. Curiel himself describes these discussions as “surprising” and “eye-opening.”
For astrophysicist Avi Loeb,
“a black hole is the ultimate prison: once you check in, you can never get out.” On the other hand, theoretical physicist Domenico Giulini regards it as “conceptually problematical to think of black holes as objects in space, things that can move and be pushed around.”
Curiel’s own take-home-message is that the very diversity of definitions of black holes is a positive sign, as it enables physicists to approach the phenomenon from a variety of physical perspectives.
However, in order to make productive use of this diversity of viewpoints, it will be important to cultivate a greater awareness of the differences in emphasis between them.
Read more at www.infowars.com
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Ken Hughes
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The laws of gravity mean that the gravitational attraction from a massive object is independent of HOW the mass of the object is distributed within itself. e.g. if the Sun were to suddenly form a black hole of the same mass, then our orbit around it would be unaffected. The only things which are pertinent to gravitational attraction are the total mass of the object and the distance away from its centre the effect is being measured.
In this case, considering the collapse of a star big enough to produce a black hole, as soon as all the mass necessary to produce a black hole is contained within the event horizon, the gravitational effects exterior to the black hole have now become permanent and are unaffected by any further hypothetical collapse of the star’s material below the horizon. The formation of any hypothetical “singularity” at the centre is irrelevant to the outside universe.
One could also argue that the final collapse necessary to produce the internal singularity can never take place, since time itself stops on the formation of the event horizon and this is slightly before the formation of the central singularity. With no time, there are no events and that means no further collapse.
Philosophically then, I conclude there is no such thing as this mathematical, hypothetical singularity at the centre of any black hole. It is pure speculation based on mathematics which is not applicable to the situation.
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Steve Crothers
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According to astronomers and cosmologists the finite mass of a black hole is concentrated in zero volume, infinite density, and infinite gravity. However, no finite mass has zero volume, infinite density, and infinite gravity. Surely this is sufficient to prove that the black hole is a fantasy. Additionally, the astronomers and cosmologists assign to their black holes two different escape velocities and no capacity for an escape velocity, simultaneously, at the same place! This too is impossible. So once again, in the simplest of terms, the black hole is a fantasy.
Crothers, S.J., Black Hole Escape Velocity, Sky Scholar, 2018,
Crothers, S.J., LIGO — Its Claims for Black Holes and Gravitational Waves | EU2017, https://www.youtube.com/watch?v=ev10ywLFq6E
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Ken Hughes
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Of course, the mathematical singularity at the centre is alleged to be of zero volume and infinite mass. Clearly, this is impossible and so the singularity at the centre is impossible. We seem to agree on that. However, the singularity at the centre does not constitute a black hole on its own. It is simply a hypothetical, mathematical forecast inside a black hole. The black hole “exists” on the formation of the event horizon and before the central singularity forms, if indeed it ever does. IMO, black holes do exist, but none of them have a singularity inside them.
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Squidly
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Hi Steve,
The LIGO experiment is fascinating. A friend of my fathers is part of the group that works on the LIGO at Hanford in Richland, WA. I have flown over and around it a few times in my father’s airplane. Pretty neat.
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Herb Rose
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A “black hole”is figment of the imagination resulting from bad theory and only exists between the ears of physicists.
A star 100 times the sun converts matter to energy and radiates that matter into space. Eventually it loses enough mass and burns down to a neutron star 7 miles in diameter. At this point it converts the last bit of mass it can Into energy and radiates it away and then it collapses into a singularity where light cannot escape its gravitational field. Since gravity is measured from the center of a mass and the mass of the singularity is less than the mass of the neutron star that produced it, the event horizon for the singularity must be less than 7 miles. That is a small target for something to hit. Say an object, we’ll use one of the voyager satellites, enters the gravitational field of the singularity. It will move towards it, just as a comet moves towards where the sun is not where it will be, but not enter the event horizon. The force of gravity causes voyager to accelerate increasing its velocity (thats how voyager escaped our solar system) and according to E=mc^2 both the energy and mass of voyager will increase. Since mass and energy can not be created or destroyed voyager’s new mass/energy must come from the singularity. If the singularity is losing mass to objects that miss its 7 mile event horizon it must have a decrease in its gravitational force and its gravitational field must shrink.
Gravity is a function of energy not mass and the only link to mass is the gravitational constant Newton created to give a source for the force he created.
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Robert Beatty
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Black holes (bh) are an emerging science helped along by great strides in recent astronomical observation techniques. One can only imagine how useful such information would have been to the likes of Albert Einstein. We need to be very careful when jumping to adamant conclusions based on old paradigms. However, we can reasonably draw new conclusions based on new observations.
Wiki advises: “A black hole is a region of spacetime exhibiting such strong gravitational effects that nothing—not even particles and electromagnetic radiation such as light—can escape from inside it. The theory of general relativity predicts that a sufficiently compact mass can deform spacetime to form a black hole.”
The comment ‘such strong gravitational effects’ is interesting, because it implies gravity effect is a variable comodity. If so, how far does its influence extend, and how does it transmit?
Then we have the statement ‘nothing—can escape from inside it’ except that astronomers have recently observed radiation emissions, as reported from sciencealert.com “For The First Time Ever, Astronomers Have Observed a Black Hole Ejecting Matter Twice. Black holes don’t just sit there munching away constantly on the space around them. Eventually they run out of nearby matter and go quiet, lying in wait until a stray bit of gas passes by.”
So how does matter apparently “disappear”. Various mathematical interpretations tell us time and volume also disappear, “mass/energy density becomes infinite”. These statements probably highlight the limitations of mathematics more than anything else.
If say, matter approaching a bh experiences such high levels of gravity that the atomic components can no longer stay attached (event horizon), then time for that mass has stopped, because the mass not longer exists in its previous form. The electrons have gone one way, the protons another (recently observed radiation emissions), and the neutrons remain adding to the bh mass. LIGO observations show bh can combine to add mass through cannibalisation.
The occasionally repeated “black holes do not exist” seems very outdated given the mounting observational evidence. BHs are certainly not fully understood, but there are regions in space where the evidence for “black hole” structure is very strong, and has defied other explanations.
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Squidly
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First, I would hesitate in utilizing “Wiki” as any sort of authority or source of accurate information on this, or any other subject.
Second, why would matter “disappear” ? .. the closer you get to a black hole, the more you slow to the observer. We know this through General Relativity. In fact, we know this observationally with other objects. So, why does this suddenly not work for a Black Hole?
Sorry, I’m not buying it, not anymore. The more I have learned about physics in general, and especially space/time, the less I believe any of the black hole hypotheses. None of them make sense in just the simplest of terms and each have internal contradictions abound.
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jerry krause
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Hi Robert,
I do not pretend to know anything about black-holes except that they are volumes of space of which (or in which) astronomers have observed nothing.
If this not the case, please illuminate me.
Have a good day, Jerry
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Robert Beatty
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Hi Jerry,
I am surprised this comment is in relation to bh and not on global cooling – which I thought would be of more import to you, given your interest in USCRN tracking.
Bh are like radio waves – invisible to the eye, but manifest in their effect.
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Squidly
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I don’t know much about “black holes”, but I would like to understand why a black hole is black. I have been told time and again that if I observe something falling towards a black hole that the closer that object gets to the event horizon, because of the enormous gravity, the slower the fall appears to me. In other words, if I were to watch you fall towards a black hole, it would appear to me that your fall would get slower and slower the closer you got until you would appear to be stuck outside of the event horizon indefinitely. I believe General Relativity predicts this as well.
So, given this, why would a black hole appear to be black? .. That doesn’t make any sense. It should appear quite bright as anything falling towards it, including light, should appear to me to be stuck just outside of the event horizon.
I know this sounds simple, but it is. I am certain there are things such as a “black hole”, but I am in great doubt that they behave even remotely like anything I have seen explained. There are so many contradictions within each of the explanations (hypothesis’) I have seen. I have yet to make sense out of any of them.
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Herb Rose
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Hi Squidify,
The time dilation only occurs on the accelerating object, not to other observers. If you were on a space ship heading into a black hole time would slow down for you but for outside observers watching your space ship it would quickly disappear into the black hole. You cannot make sense out of nonsense.
A while ago scientists were talking about empty areas of space. New telescopes were developed and the “empty” areas of space turned out to be full of stars and galaxies.
The speed of light is not constant so all of Einstein’s theories are wrong.
Since light does not travel in a straight line how do you know what a straight line is? Nothing in the universe travels in a straight line and Newton’s assumption that an object will continue in a straight line unless a force acts upon it is wrong. Gravity is a function of energy, not mass, and an object will maintain its energy unless energy is added to it or it loses energy to another object.
Have a good day,
Herb
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Squidly
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Interesting Herb. You should inform the Science Channel about their incorrect depictions in their “How The Universe Works” series because in several of them they explicitly explain how an observer would see their buddy falling into a black hole indefinitely. Not just the Science Channel, but several other sources, including NASA and others, describe this exactly the same way as I did above.
Perhaps you should educate them Herb, because it seems there are a whole lot of astrophysicists that contradict what you have just said.
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Squidly
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And by the way Herb, all of the extra mumbo jumbo you just spouted on about has nothing to do with my original comment. Do you just like listening to yourself talk too?
But to respond, I would have to say I agree with some of what you said, but much of it is just a bunch of nonsensical blather.
Thanks though .. I appreciate the response!
Oh, and my name is not “Squidify” there Herby …
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Herb Rose
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Hi Squidly,
Sorry for the misspelling of your name. My eyes are not that good and the small type is hard to distinguish. Spell check tells me that any way I spell your name is wrong.
The black hole time dilation is from special relativity, E=mc^2, not general relativity which is Einsteins attempt to account for gravity.
According to Einstein the speed light is constant and is the basic reference for everything else. If you were on an object traveling at half the speed of light and shined a light forward, you would see that light move at the speed of light. An observer on the ground would observe you moving at half the speed of light and the projected light moving at the speed light not 1.5 times the speed of light. The speed of light is the constant reference for all and time, distance, and mass change not the speed of light.
When you add energy to an object, the faster the object is moving the more of the energy is converted into mass not velocity. An object with mass can never achieve the speed of light, as more energy is converted to mass which necessitates more energy to accelerate. An object with no mass (photon) cannot go slower than the speed of light (in a vacuum) because there is no negative mass..
The observer being sucked into the black hole does not realize that his mass is growing, time is slowing down and distance is shrinking because in his frame of reference the speed of light remains the same. For that observer he never reaches the event horizon but for an observer watching from outside his perspective, with a different reference of the speed of light, there is no time dilation and he observes the object accelerating into the event horizon.
You cannot make sense of it because it is nonsense and why in physic it is acceptable for all perspectives to be valid. That is relativity where everything is referenced to the speed of light for the observer.
Have a good day,
Herb
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Squidly
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Sorry Herb, but again, I just reviewed about a dozen sources that all make the same claim .. if Herb were to fall into a black hole and I where watching Herb from say a ‘safe’ distance (or even a million or two light years away), I will see Herb falling into that black hole for the rest of my life because Herb would appear to stick to the outside of the black hole without ever falling into it. Go look for yourself Herb. Here is but one episode on the Science Channel that will tell you exactly what I just described. https://www.youtube.com/watch?v=6wUbo4VewQU
So, what you say does not align with what virtually every physicist tells us about gravity and space/time. Again, if any of the 4 hypotheses of black holes were consistent, then a black hole would not be “black”, it would be very bright as we would continue to observe hot gasses falling into it, virtually forever. The point is, since we do not observe these things, the black hole hypotheses are flawed. There are many other ways they are flawed as well .. but this just being a painfully obvious one.
Squidly
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Just watched on my my favorite movies again, “Interstellar” .. When Cooper, Brand and the other guy venture down to the water planet near Gargantuan (supermassive black hole) they age at the rate that would be normal to them, about 3hrs 15min, but their observer who is outside of the gravitational field of Gargantuan on the mothership aged 23 years! … This was illustrating precisely General Relativity. To the observer on the mothership outside of Gargantuan’s effect, Coope, who that went to the planet surface, would look to him like he was barely moving. The closer Cooper gets to Gargantuan, the slower Cooper would appear to move. Again, Cooper only aged 3hrs 15min while the observer aged over 23yrs !!!
This illustrates exactly what we have observed and can actually measure. It has been done! .. I don’t care if Einstein’s theories are wrong. In this particular case, this particular phenomena, we have observed and measured it empirically. In this particular case, Einstein was absolutely correct. We know this for fact.
Again, if you are falling into a black hole, and I am watching you from outside of the gravitational field of that black hole, that closer you get to the event horizon the slower you appear to me. To the point where is would take hundreds of years (my years) for you to move a foot. If you were looking back at me, I would begin moving extremely fast and I would age very quickly until I simply disappeared in a blip. You would seem to age normally. You would feel as if nothing was different for yourself.
As I have said, this phenomena has been measured. Clocks in Death Valley run slower than clocks on Mt. Everest. If I lived in Death Valley and you live on the top of Mt. Everest, I will age slower than you.
Robert Beatty
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Nobody is being asked to buy anything.
All we have to do is maintain an open positive mindset, and fairly assess any new information as it arrives.
Black holes may turn out to be one of the greatest and far reaching physics investigations of the modern era.
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Squidly
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I would agree with you Robert. I would also agree that physicists currently have no clue as to what Black Holes are or how they behave. None of the 4 Black Hole hypotheses can coexist with any of the Big Bang Universe or Static Universe hypotheses. None of them can coexist, so clearly there are some fundamental problems going on here.
I laugh at people like Herb who pretend they understand these things. I have my own hypotheses about these things myself, but I would not be so narcissistic to even pretend to understand them. Nobody on Earth understands them.
That being said, we continue to learn a lot along the way. Black Hole research has led to many other discoveries and understandings. I am sure it will continue to do so, even if we never learn the truth about Black Holes themselves.
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Robert Beatty
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Squidly, I am aware of two Kerr bh proposals as well as Einstein’s singularity result. Stephen Hawking developed a theory involving quantum perturbations. Are these your four? “I have my own hypotheses about these things myself.” Don’t be shy, your fifth suggestion might be the one that brings the bacon home.
My PROM paper effort does not include a ‘big bang’ component, but appears to coexist with a Static Universe.
See https://principia-scientific.com/wp-content/uploads/2018/02/PROM-Gravispheres.pdf
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Squidly
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Very nice Robert! .. Thank you for the link to your paper. Very interesting indeed.
My only point in all of this is that there is far more we do not know than what we do know, and things we think we know appear to be very contradictory to other things we think we know. In the case of “Black Holes”, I do not believe we have even the first clue as to what they are. I do not contend that they do not exist, I believe they do. But I also believe that in many cases we have allowed our imaginations to runaway with ourselves, which is fine, but don’t try to turn imagination into definitive proclamations of fact, as cosmologists love to do. Black Holes are things we have little to no understanding of.
We are bombarded by proclamations that our universe began with a “Big Bang”, and yet there is scant evidence of such and many internal contradictions within the hypotheses (not to mention the logical contradictions). We are told this “Big Bang” began from a singularity with infinite heat and zero volume. However, we also know that in order to have heat we must have matter and energy, which necessarily dictates volume.
We are bombarded by proclamations that our universe is full of “Black Holes” that possess infinite gravity and again, zero volume (singularity). Many of these things, besides not adding up mathematically, don’t make logical sense, and yet they are treated as if they are definitive. Whenever things like this are treated as absolutes, it sends up red flags for me, especially for things like these for which we have little to no knowledge. As soon as you inject “infinite” into the equation, you have found you know nothing about that which you speak.
Let me give an example. We are told there is a “background radiation” from the “Big Bang” of our universe, right? .. But then we find that intergalactic space is not empty, not empty at all. In fact intergalactic space is filled with all sorts of gases and dust. Not just gases and dust, but very hot gases and dust. So, is this so-called “background radiation” really a signature of the “big bang” ? .. Or is it simply the signature of all of the intergalactic gases and dust? .. I have not seen where anyone has considered this, instead they make proclamations and definitive statements about the “cosmological background radiation is a signature of the Big Bang”, as if it were definitive fact.
Another topic, “dark matter”. We have been told for years that scientists have discovered “dark matter”, something we cannot see nor detect but it makes up over 60% of the mass of our universe. Low and behold, practically on a daily basis, astrophysicists and cosmologists are finding all sorts of masses that they hadn’t found before, disproving their own “dark matter” hypotheses, and yet we are still presented “dark matter” as if it were definitive fact.
I particularly don’t hold cosmology in very high regard for the most part. Sure, I find the subject extremely fascinating, but then I have always found Star Trek to be equally fascinating. Both may be nothing but our imagination.
But I digress … Much to learn Robert .. Much to learn.
Thank you again! .. I very much appreciate you sharing your paper!
Squidly
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Hi Squidly'
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In reference to your comment on your favorite movie. It is not gravity that causes a time dilation but velocity. It all is a result of the speed of light being constant. The gravity of a singularity is providing the energy to increase the velocity of an object moving towards it which in turn causes the time dilation. I have submitted another article to PSI to try to explain this further. We’ll see if t gets published.
Have a good day,
Herb
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Robert Beatty
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You raise many good points Squidly, The common thread seems to be humans’ innate drive to find explanations for what appears as inexplicable evidence. Religions and Native Lore are replete with examples of mythical explanations.
This tradition extends to scientific research, which is mostly constructed around ‘certainties’ and reported as such. This does not mean they cannot be questioned, which is the great strength of our scientific research methodology.
However; that is unless they are part of a religion, or ancient paradigm. In that event ‘certainties’ become sacrosanct and critics are demonised. Mmm that sounds kind of familiar.
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