I read Sabine Hossenfelder’s latest blog post yesterday. The title was A brief history of black holes. I left a couple of comments. One was a reply to Louis Marmet, and referred to Oppenheimer’s 1939 frozen star black hole. I said I think the black hole grows like a hailstone, from the inside out. The other was addressed to Hossenfelder, and referred to Einstein talking about the variable speed of light. I said that IMHO this had to mean Penrose/Hawking singularity theorems were wrong. I found that neither comment appeared. Hence I thought I’d spend a little time going through the blog post giving my thoughts. I’m black, with blue hyperlinks. Hossenfelder is green:
The possibility that gravity can become so strong that it traps light appears already in Newtonian gravity, but black holes were not really discussed by scientists until it turned out that they are a consequence of Einstein’s theory of general relativity.
This is wrong from the off. Einstein made it crystal clear that a gravitational field is a place where the speed of light is spatially variable. Have a read of this Wikipedia article:
Like physicsFAQ editor Don Koks says, “light speeds up as it ascends from floor to ceiling”. In a strong gravitational field, it speeds up all the more, so strong gravity doesn’t trap light. That’s not to say black holes don’t exist. But they don’t exist because gravity is strong. They exist because they’re a place where the “coordinate” speed of light is zero. Note though that Einstein talked of the speed of light, not the coordinate speed of light. Light doesn’t behave like a ball that slows on the way up and goes faster on the way down. By the by, the local speed of light is not always c. A stopped observer doesn’t see light moving at c. He sees nothing. Ever. Zero divided by zero is not one.
General Relativity is a set of equations for the curvature of space and time, called Einstein’s field equations. And black holes are one of the possible solutions to Einstein’s equations. This was first realized by Karl Schwarzschild in 1916. For this reason, black holes are also sometimes called the “Schwarzschild solution”.
This is also wrong. General Relativity is a theory of gravity, not a set of equations for the curvature of spacetime. Curved spacetime is a curvature of the “metric”. Gravity is real, but the metric is an abstract thing, associated with measurement. Think of it as a curvature in your plot of your measurements of space and time. Imagine you could place a 15 x 15 array of optical clocks throughout a horizontal slice of space around the Earth. Then you plot all the clock rates, such that the lower slower clock rates generate data points lower down in a 3D image, and the higher faster clock rates generate data points higher up in the 3D image. When you join the dots, your plot looks like this:
CCASA image by Johnstone, see Wikipedia
That’s your typical Riemann curvature tensor image, the “rubber-sheet” depiction of curved spacetime. But it’s derived from optical clock rates, so what it’s really plotting is the variable speed of light. It isn’t plotting curved space and curved time. That’s why Einstein said a gravitational field is a place where space is “neither homogeneous nor isotropic”. Not a place where space is curved.
Schwarzschild of course was not actually looking for black holes. He was just trying to understand what Einstein’s theory would say about the curvature of space-time outside an object that is to good precision spherically symmetric, like, say, our sun or planet earth. Now, outside these objects, there is approximately no matter, which is good, because in this case the equations become particularly simple and Schwarzschild was able to solve them.
Hooray. The curvature of spacetime. Not the curvature of space and the curvature of time. A gravitational field is a place where space is “neither homogeneous nor isotropic”. Not a place where space is curved.
What happens in Schwarzschild’s solution is the following. As I said, this solution only describes the outside of some distribution of matter. But you can ask then, what happens on the surface of that distribution of matter if you compress the matter more and more, that is, you keep the mass fixed but shrink the radius. Well, it turns out that there is a certain radius, at which light can no longer escape from the surface of the object, and also not from any location inside this surface. This dividing surface is what we now call the black hole horizon. It’s a sphere whose radius is now called the Schwarzschild radius.
There’s nothing wrong with that. Apart from the explanation for why the light can’t escape. It’s because the speed of light at the event horizon is zero. So the vertical light beam doesn’t ascend from the event horizon. And remember this: the speed of light can’t go lower than zero. That’s important. Light can’t go slower than stopped.
Where the black hole horizon is, depends on the mass of the object, so every mass has its own Schwarzschild radius, and if you could compress the mass to below that radius, it would keep collapsing to a point and you’d make a black hole.
Who says it would keep collapsing to a point? It wasn’t Einstein. It wasn’t Oppenheimer either. It was Penrose and Hawking. Two guys who were doing their own thing, and had clearly never read what Einstein said.
But for most stellar objects, their actual radius is much larger than the Schwarzschild radius, so they do not have a horizon, because inside of the matter one has to use a different solution to Einstein’s equations. The Schwarzschild radius of the sun, for example, is a few miles*, whereas the actual radius of the sun is some hundred-thousand miles. The Schwarzschild radius of planet Earth is merely a few millimeters.
No problem. The Schwarzschild radius of the Sun is circa 1.9 miles, and the Schwarzschild radius of the Earth is circa 9 millimetres.
Now, it turns out that in Schwarzschild’s original solution, there is a quantity that goes to infinity as you approach the horizon. For this reason, physicists originally thought that the Schwarzschild solution makes no physical sense. However, it turns out that there is nothing physically wrong with that. If you look at any quantity that you can actually measure as you approach a black hole, none of them becomes infinitely large. In particular, the curvature just goes with the inverse of the square of the mass. I explained this in an earlier video. And so, physicists concluded, this infinity at the black hole horizon is a mathematical artifact and, indeed, it can be easily removed.
It can only be “easily removed” by using tortoise coordinates. That’s seconds of infinite length, which is total crap. You cannot get rid of infinite gravitational time dilation by introducing smoke-and-mirror seconds of infinite length. Not unless you’re a mathematical quack peddling total garbage.
With that clarified, physicists accepted that there is nothing mathematically wrong with black holes, but then they argued that black holes would not occur in nature because there is no way to make them. The idea was that, since the Schwarzschild solution is perfectly spherically symmetric, the conditions that are necessary to make a black hole would just never happen.
That’s what Einstein said in his 1939 paper on a stationary system with spherical symmetry consisting of many gravitating masses. For some reason he missed the significance of Oppenheimer and Snyder’s 1939 frozen star paper on continued gravitational contraction. Maybe it was because war was looming, and he had other things on his mind. I don’t know. But I do know he should have predicted gamma ray bursters. Because falling bodies don’t slow down. And because those falling bodies are falling because the speed of light is reducing. He missed the trick. Maybe that was his greatest blunder. The irony is that the detection of gamma ray bursters reawakened interest in general relativity in the 1960s. In fact, that’s why Hawking proposed his Hawking radiation. See his 1974 Nature paper on black hole explosions?
But this too turned out to be wrong. Indeed, it was proved by Stephen Hawking and Roger Penrose in the 1960s that the very opposite is the case. Black holes are what you generally get in Einstein’s theory if you have a sufficient amount of matter that just collapses because it cannot build up sufficient pressure. And so, if a star runs out of nuclear fuel and has no new way to create pressure, a black hole will be the outcome. In contrast to what physicists thought previously, black holes are hard to avoid, not hard to make.
This is incorrect in that Penrose and Hawking proved nothing, because they did their own thing and ignored Einstein. But it is correct in that black holes are what you get if a big star runs out of fuel. The issue of course is this: is there a point singularity in the middle of a black hole? The answer has to be no, because light can’t go slower than stopped. At the event horizon there is no more gradient in the speed of light, so no gravitational field. So now you know why all that stuff about an elephant in two places at once is absolute nonsense:
Image from the New Scientist article the elephant and the event horizon
The bottom line is this: if there’s a paradox, there’s something wrong somewhere. Probably something seriously wrong, right at the beginning.
So this was the situation in the 1970s. Black holes had turned from mathematically wrong, to mathematically correct* but non-physical, to a real possibility. But there was at the time no way to actually observe a black hole. That’s because back then the main mode of astrophysical observation was using light. And black holes are defined by the very property that they do not emit light.
There’s some rewriting of history here. See the 1971 Physics Today article introducing the black hole by Remo Ruffini and John Wheeler who said “in this sense the system is a frozen star”. This sort of thing is par for the course in contemporary physics. When you’ve read the old papers, you realise how bad it is.
However, there are other ways of observing black holes. Most importantly, black holes influence the motion of stars in their vicinity, and the other stars are observable. From this one can infer the mass of the object that the stars orbit around and one can put a limit on the radius.
No problem with that. That’s what Sagittarius A* is all about. See the animations produced by Andrea Ghez and team at the UCLA Galactic Center Group using Keck datasets:
Animation by Andrea Ghez and research team at UCLA
There’s something there with a mass that’s circa 4.28 million times the mass of the Sun. But it’s at most thirty times bigger than the Sun in terms of spatial extent. There’s only one thing it can be, and that’s a black hole. Hence we’re confident that black holes exist. As to their exact nature, that’s another story.
Black holes also swallow material in their vicinity, and from the way that they swallow it, one can tell that the object has no hard surface.
You can’t tell what’s inside the black hole from observations of infalling bodies. However you can surely say something about gamma ray bursts. See the 2013 AMPS paper an apologia for firewalls. Tucked away in the conclusion is footnote 31, containing a reference 87 to Friedwardt Winterberg’s 2001 paper gamma ray bursters and Lorentzian relativity. Winterberg talked about the direct conversion of an entire stellar rest mass into gamma ray energy: “if the balance of forces holding together elementary particles is destroyed near the event horizon, all matter would be converted into zero rest mass particles which could explain the large energy release of gamma ray bursters”. I’m sure Winterberg is essentially correct. Unfortunately he gets no publicity. He gets “studiously ignored” instead whilst people like Hossenfelder pretend to be the expert and suck up to Penrose.
The first convincing observations that our own galaxy contains a black hole came in the late 1990s. About ten years later, there were so many observations that could only be explained by the existence of black holes that today basically no one who understands the science doubts black holes exist.
Again, no problem with that, but see Peter Erwin’s comment about Cygnus X-1. The issue is the nature of black holes. I say they’re frozen stars, others say they’re point singularities. I say point singularities contradict Einstein’s general relativity.
What makes this story interesting to me is how essential it was that Penrose and Hawking understood the mathematics of Einstein’s theory and could formally prove that black holes should exist. It was only because of this that black holes were taken seriously at all. Without that, maybe we’d never have looked for them to begin with. A friend of mine thinks that Penrose deserves a Nobel Prize for his contribution to the discovery of black holes. And I think that’s right.
I don’t. I think Penrose did his own thing and appealed to Einstein’s authority whilst flatly contradicting the guy. That was his MO. See MTW, which refers to Eddington-Finkelstein coordinates. Box 31.2 on page 828 says Eddington and Finkelstein used free-falling photons as the foundation of their coordinate system. Only those photons aren’t falling faster and faster, they descend slower and slower. Also see the Wikipedia article, which says this: “they are named for Arthur Stanley Eddington and David Finkelstein, even though neither ever wrote down these coordinates or the metric in these coordinates. Roger Penrose seems to have been the first to write down the null form but credits it (wrongly) to the above paper by Finkelstein, and, in his Adams Prize essay later that year, to Eddington and Finkelstein”. Penrose was making it up as he went along. Yea verily. If that isn’t enough, have you ever sat down and taken a long hard look at Penrose diagrams which plot the route to the parallel antiverse?
Penrose diagram from the CERN courier article Physics in the multiverse, image credit Andrew Hamilton
FFS. The parallel antiverse. The word that springs to is charlatan. As for Hawking, see his singularities and the geometry of spacetime dating from 1966. On page 76 he talked of “such a strong gravitational field that even the ‘outgoing’ light rays from it are dragged back”. It’s clear Hawking didn’t understand the first thing about gravity, and had never read what Einstein said. He was winging it, and getting an easy ride on account of the wheelchair.
* Unfortunately, a mistake in the spoken text.
No problem. But what is a problem, is so-called physicists like Hossenfelder peddling horseshit on the internet and censoring those who refer to bona-fide papers and point out the issues. This sort of thing is endemic. There isn’t just something rotten in the state of QED. There’s something rotten in the state of physics. Safe spaces and no-platforming is how these guys have been operating for fifty years. It truly is the trouble with physics.
PS: If all this is new to you, you might want to take a look at this:
The speed of light is not constant
How gravity works
The principle of equivalence and other myths
Black holes
Hawking radiation
The Hawking papers
The information paradox
Firewall!
I’ve noticed a curious pattern with Dr. Hossenfelder in her videos. Several years ago she dressed as a plain jane and came across as strictly academic. She often collaborated with her colleague friends.
Then her personal appearance became much more glamorous, the videos are now slickly produced,the videos were all about her expertise, and she even began to do singing presentations!(PUKE!) My take is it’s now all about celebrity first, truth distant second. £-$-£ to infinity and beyond.
I think you’re spot on there, Greg. Yes, it’s celebrity first, and truth a distant second. For myself I don’t mind Sabine Hossenfelder’s videos, or the singing. I don’t like them, but that’s up to her. It’s her choice. What I do dislike is the way she censors factual informative comments that point out issues with what she’s saying. Peter Woit is the same. Ditto for Matt Strassler, Luboš Motl, and others. This sort of thing seems to be endemic with academics. It seems like propaganda and censorship is their way of life. It seems like they’re all self-appointed experts engaged in self-promotion, who have a massive intellectual arrogance, and who brook no challenge. Even when they’re peddling abject nonsense.
Sabine Hossenfelder said this on her blog: Several people have tried to submit comments to this thread which contain links to websites I don’t recognize. I want to remind you all that I don’t approve links except those to journals, the arXiv, or well-known newspapers. When in doubt, please consult the comment rules.
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So let’s try this:
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Louis: I think it’s straightforward myself, because I think Oppenheimer and Snyder’s original “frozen star” black hole is correct. See On Continued Gravitational Contraction dating from 1939. It was no flash in the pan – see the 1971 Physics Today article Introducing the black hole by Remo Ruffini and John Wheeler. They said “in this sense the system is a frozen star”. There is no central point singularity. But there is a black hole. It grows from the inside out, like a hailstone. Imagine you’re a water molecule. You alight upon the surface of the hailstone. You can’t pass through this surface, but soon you’re surrounded by other water molecules, and eventually you’re buried by more. So whilst you can’t pass through the surface, the surface can pass through you. I can’t explain why Einstein missed this in his 1939 paper On a stationary system with spherical symmetry consisting of many gravitating masses. Or the prediction of gamma ray bursters. Perhaps it was because war was looming and his mind was elsewhere.
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Of course, Einstein’s “spatially variable” speed of light must mean Penrose/Hawking singularity theorems are wrong. That’s because in a gravitational field the ascending light beam speeds up. In a strong gravitational field, the ascending light beam speeds up even more. It doesn’t get dragged back, like Hawking said on page 76 of his 1966 paper Singularities and the geometry of spacetime. See Is The Speed of Light Everywhere the Same? by PhysicsFAQ editor for something contemporary on this.
Hopefully John, she will let your newest comments in. Better yet she actually acknowledges her mistakes, but unfortunately I doubt it.
Here’s a couple of new b.s. articles that made me giggle. 1.) On the New Scientists site a claim at hints of possible new forces to add to the Standard Model. It also claims that gravity still can’t be explained! Of course I would have to subscribe to be enlightened on what the new 4th,5th,or even 6th levels of quantum energies might possibly be . Poor me, I guess I shall intentionally remain an ignoramus by not subscribing. Talk about bollocks in the form of clickbait. 2.) On SciTechDaily, the exiting newest life changing discovery is Higg’s Spectroscopy! Brought to us by the esteemed physicists at HZDR & MPI-FKF ! What a bunch of happy horseshit! What’s next, Higg’s Colonoscopies?
I am seriously thinkin about leaving the trucking & logistics industry to become a Celebrity Quantum Physicist, I’ve been told for years I have a genuine talent for blowing smoke up other people’s arses…………….
Oh LOL! I am rolling around laughing here. Yep, the science media is full of horsesh*t. They have a symbiotic relationship with physicists peddling woo. As to why, well, New Scientist said when they put the word quantum on the cover, sales go up. What are they saying now? I see the article. It’s the usual Goebbelesque nonsense. Hence I’m no longer a subscriber. Mind, you, this was good in SciTech Daily: Russian Astrophysicists Trace Neutrinos – Mysterious “Ghost Particles” – From Where No One Had Expected. I expected neutrinos from gamma ray bursts. See https://physicsdetective.com/firewall/.
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Yep, that latest comment of mine appeared on Backreaction. There’s a new post now, so a brief of history of black holes is history.
Neutrinos possibly being expelled out from the lowest end of the electromagnetic spectrum? Very intriguing indeed. The next question I would ask : does it have to occur during a massive,cataclysmic event, or at any transmission of radio waves? Do the neutrinos occur in any other spectrum emissions, or even thru all spectrums? Not just cataclysmic gamma bursts you and others have written about. We need to pay continuing attention to these fine folks in Russia.
The neutrinos aren’t being expelled from the electromagnetic spectrum, Greg. It would be something like a forced beta decay. If you were falling into a black hole, your neutrons would disintegrate first. Then your electrons. Then your protons. There would be transient pions etc, but you would end up as a bunch of photons and neutrinos departing in different directions at the local speed of light. The same would happen to much of the matter of a collapsing star. Think of each particle as a disintegrating flywheel. Angular momentum is conserved because the parts fly off in those different directions. The parts would fly off in different directions for an electron as opposed to a positron.
Thanks for the clarification John ! After a carefull reread I think know were I went wrong? I conflated the act of emergence of the neutrinos at the same time as the radio waves,with the production source of neutrinos (forced beta decay) ,with the production source of photon based radio waves? Two completely different particles and processes .
I do want to be accurate with my statements, even if it does make my cerebral neurons scream in agony from even remedial usage………..
So if mass turns into gamma ray bursts on falling into a black hole, what makes a black hole increase in mass like a hailstone? Does some of the gamma ray energy enter the black hole and increaes its mass? Does other massless radiation passing by hit the black hole and turn into mass on its surface -eg. radiation frozen onto the surface of the black hole?
Yes, IMHO some of the gamma rays or neutrinos add to the black hole. Radiation is “frozen onto the surface”, as it were. Then more radiation comes along, and the original radiation ends up below the surface, as per the hailstone analogy. The same applies to matter at the center of a collapsing star. In my view there’s not much difference between radiation and matter. Radiation is akin to a pressure pulse in space propagating linearly through space at c, which reduces in line with gravitational potential. Matter is radiation in a closed path. I don’t know if you’ve read https://physicsdetective.com/what-energy-is/, but at the fundamental level, I see space and energy as the same thing. So the interior of a black hole is akin to dense frozen space in which there is no motion.
But the black hole moves through space?
Edit: Okay, just saw comments below.
Your favored theory of the frozen star black whole should make some significant and testable predictions, no? I think once it’s figured out how an object with a local surface speed of light of zero can move through space, and you rectify the paradoxical event horizon radii dependant on reference frame, you should find momentum will interact with the other parameters of a black whole, rather than momentum being an independent parameter.
Also, just curious, have you read Thomas Kuhn’s Structure Of Scientific Revolutions? It very cogently discusses why paradigms in science, once adopted aren’t questioned until some specific conditions are usually met, all as matter of efficiency.
It seems the current paradigm in quantum physics is a bit of a cargo cult science. Paradigm emergence in science seems to follow a pattern of increasing disagreement around the old paradigm, followed by a coalescence of agreement around the new paradigm. Quantum physics has never had a real consensus; with the dozens of interpretations and ontologies in disagreement from the very beginning. The appearance of consensus is constantly emphasized in every class you could take on the subject. It’s pounded into knew students if science constantly that QM is the best theory we’ve ever had and to question it means you don’t understand it, but no one really understands it, so don’t be surprised that it doesn’t seem quite right.
I think the two places where from a new paradigm will emerge are particle physics and quantum optics. Particle physics follows an absurdly bad model with dozens of invented free parameters to get the Standard Model to agree with experiment. But it is also an incredibly profitable field, that’s had success getting billions of dollars from government funding, and because of that, it’s not likely anytime soon to admit their paradigm is wrong.
Quantum optics on the other hand uses very cheap apparatuses and conducts experiments that are close to probing the fundamental nature of mass, stress energy properties of the vacuum, and variance in c.
Hi Eric. There’s some good points in your comment.
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As for significant and testable predictions for the frozen star black, try this: black holes don’t fall down. There’s no dynamical motion inside the black hole like there is inside an electron. So the mechanism by which a body falls down just isn’t there. However I don’t see an issue with the black hole moving through space. An iceberg moves through the sea, even though the water in the iceberg is frozen.
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As for the paradoxical event horizon radii dependant on reference frame, I think that’s based on a misconception. The event horizon is where light is stopped, and that’s that. A stopped observer does not see a stopped clock ticking normally. Zero divided by zero is not one. The Schwarzschild singularity is not merely some abstract artifact of some abstract coordinate system. It’s real.
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Yes, I’ve read Thomas Kuhn’s Structure Of Scientific Revolutions. I think his point is broadly correct, but I don’t know if it’s quite appropriate to the current situation. So many paradigms are set in stone by Nobel prizes and monumental vested interest. I’d say that’s why the current paradigm in quantum physics is now cargo cult science. It isn’t going to be easy to fix. Like you said, particle physicists are not likely any time soon to admit that their paradigm is wrong. Yes, quantum optics sounds more promising. I’ve noticed work by Aephraim Steinberg et al and by Jeff Lundeen et al. I don’t know if they count as quantum optics guys, but I think they’re on the right lines. I wish people like that got more publicity. And other people too. I know bona-fide professional physicists who cannot get their papers into high-impact journals, and who struggle to obtain media attention. The situation is not good. Meanwhile physics is withering on the vine. Which is why people like me try to do their bit I suppose.
Hey John, as far as the subject of media attention goes, I have two mostly lame thoughts: 1.) Have you or your like minded colleagues who can’t get published ever thought about going in the opposite media direction and start a Face Book or You Tube page(s) ? I know it’s not very professional or overly academic, but do you think stooping that low would help? At least it is exposure. 2.) After watching Dr.Sabine’s latest YouTube post about “Is faster than the speed of light possible?”, she definitely has mastered the art of exposure. That cheeky little minx!
I have, Greg. There are some great YouTube guys out there, like Destin Sandlin from Smarter Every Day. I was looking at video cameras a while back. But I’ve been busier recently with work work, and haven’t done anything about it. I don’t have an issue with YouTube physics being “not very professional or overly academic” etc. It’s just another medium, and I would like to counter some of the really lame lies-to-children garbage we see from the likes of Don Lincoln. I just don’t have enough free time at the moment.
Cool, I look forward to that day. And if you do decide to become a You Tuber, I will gladly contribute a meager monetary amount if you go the patronage route.
I have read several of your articles and I believe you are correct but I still have some questions.
1. I believe the energy-stress tensor is ultimately about electromagnetic wave densities. Are you saying that the higher the density of electromagnetic waves the slower the speed of light waves? How does this density slow the speed of light?
2. At the surface of a black hole and below its surface you say the motion of light is zero. I would think if light stopped all motion it would no longer be an electromagnetic wave and would cease to exist. Poof! What is your concept? Is it possible that light slows but never gets to zero?
3. As light slows does the dimension of space shrink? Is a black hole a hollow empty shell?
Are you saying that the higher the density of electromagnetic waves the slower the speed of light waves? Not quite. I’m saying the higher the energy-density of space, the slower the speed of light waves. Of course, if you pushed a zillion photons into a small location, you will achieve this.
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At the surface of a black hole and below its surface you say the motion of light is zero. I would think if light stopped all motion it would no longer be an electromagnetic wave and would cease to exist. Poof! What is your concept? My view is that it still exists as a region of space where the spatial energy-density is higher than usual. I view the photon as a pressure-pulse of space propagating through space.
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Is it possible that light slows but never gets to zero? I don’t think so. Because black holes are black. The upward light beam doesn’t get out.
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As light slows does the dimension of space shrink? Is a black hole a hollow empty shell? I don’t think so. I think it’s more like “solid space”. I view space and energy as the same thing. If you haven’t already, take a look at this article: https://physicsdetective.com/what-energy-is/
Thanks for the answers. I have a continuing question.
1. I see your point that all types of energy density will add to the slowing of light. So you say a black hole is composed of very highly stressed spaces. I have difficulty understanding the stress-energy-momentum tensor matrix but I think that in a black hole all the momentum vectors are zero and only pressure is left to be measured as energy. Even if there are other stresses that I don’t know about, how do non-moving highly stressed spaces attract other non-moving highly stressed spaces and create what we call gravity to hold a black hole together? What prevents the black hole from exploding?
Donald: I view space as something like a gin-clear ghostly elastic medium. See Robert Close’s 2009 elastic space paper:
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https://link.springer.com/article/10.1007/s00006-010-0249-1
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Light propagates through space like any other wave propagates through an elastic medium. Hence Maxwell’s expression for the speed of light V =√(m/ρ), where “m is the coefficient of transverse elasticity, and ρ is the density”. For the wave to propagate, space must have the properties of both stress and tension. That tension is in essence the strong force. It keeps a proton together, but you can annihilate a proton with an antiproton to yield gamma photons. That strong force tension doesn’t then disappear, it keeps the photon together, and it keeps it propagating at the speed of light. That tension is still there even when V (=c) is zero and space is unyielding. That’s what keeps the stress, which is a directional pressure, contained. Or at least I think it does. Maybe 13.8 billion years ago, it didn’t.
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PS: I also think of a gravitational field as a stress or pressure gradient in space. But please note that I do find it rather difficult to ascribe qualities like stress and pressure and tension and energy density or just density to space. You can’t define it in terms of other things. IMHO space isn’t made of things. Things are made of space.
“IMHO space isn’t made of things”
No, it is a multi dimensional Riemannian Manifold composed one or more fields – gravitational, electromagnetic, Higgs,… We have observed and measured the effect it has on electromagnetic radiation. The radio astronomy of Pulsars and Fast Radio Bursts (FRB) reveals that shorter wavelength components of the pulse arrive before longer wavelengths. This effect is proportional to the distance of the object from the observer. It is also isotropic.
IOW, the interstellar and intergalactic media have an index of refraction greater than unity.
Main takeaway? Zwicky and Hoyle were right. The Big Bang never happened.
“No, it is a multi dimensional Riemannian Manifold composed one or more fields – gravitational, electromagnetic, Higgs…”
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I don’t think it is Roy. Einstein said a field is a state of space, and I think he was right about that. I also think space can’t have two different states at the same location. For the cherry on top, I think that a Riemannian Manifold is an abstract thing, and it doesn’t help to define something real in terms of something that isn’t.
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See what you make of this: What Energy Is. At the fundamental level, I have trouble distinguishing it from space.
PD,
I should have written that space is the net of the fields, they differing chiefly in the instruments we use to measure them.
The point I was trying to make is that we have evidence that space is nowhere the vacuum that Einstein had in mind. It was that particular point that swayed the argument between recessional velocity and tired light as the cause of the red shift. No Big Bang.
Noted Roy. Have a read of this article about Einstein’s 1930 lecture in Nottingham. It says this: “The strange conclusion to which we have come is this: that now it appears that space will have to be regarded as a primary thing and that matter is derived from it, so to speak, as a secondary result”. IMHO it’s like space is this gin-clear ghostly elastic thing, photons are waves in it, and are electrons etc are photons in a closed path. As far as I know the general idea started with William Kingdon Clifford’s space theory of matter dating from 1876. See Wikipedia.
Interesting article, John. Was this at the beginning of Einstein’s search for a unified field theory? I copy from the article:
“We want a system of equations which will take in all physical phenomena. This would be an enormous gain in the picture of the uniformity of physical nature.”
This would require a pinball/compact particle universe. I sense/intuit that your view is closer to the truth, although I incline towards tequila. The inclusion of wave functions in the mappings increases the computational complexity (my field) up a notch or two, probably to the point that we’d watch the blinking lights for a long, long time (10^N BB universes) before they settled on 42. And that’s just to find out if you wanted a twist. You just have to accept that there are things that we will never know.
I’m not sure Roy. I’ve tried to find out about Einstein’s unification attempts, but without much success. I read Einstein’s Unification by Jeroen van Dongen, but found it unrewarding. Maybe that’s my fault, I’m not sure.
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Sorry, what’s a pinball/compact universe? My view is in essence William Kingdon Clifford’s Space theory of Matter. There are waves in space. We call them light. But when they’re in a closed path, we call them matter. As for wavefunction, I’m with Jeff Lundeen: “We hope that the scientific community can now improve upon the Copenhagen Interpretation, and redefine the wavefunction so that it is no longer just a mathematical tool, but rather something that can be directly measured in the laboratory”.
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Yes, I accept there are things that we will never know. Whilst I’m happy enough with the expanding universe, I’m not satisfied with Big Bang cosmology. The $64,000 question is of course what banged?
John, this comment system is driving me crazy. I just spent an hour formulating a reply. I clicked the post comment, forgetting to check the Captcha box. It was offended and to demonstrate it threw away everything that I had written.
I’m awfully sorry Roy. It hacks me off that here we are in the 21st Century, and software is in general much flakier than it used to be. Instead of making sure it works, developers piss about changing things for no good reason.
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But if it’s any consolation, your post disappeared because it was deemed to be spam. I can’t see why. But I have flagged it as not spam. Even my comments get flagged as spam. Grrr. But without that spam filter, things can real bad real fast. I had literally hundreds of medical spam comments a while back. Hundreds. Now before I post, I save my comment. I do this everywhere these days. Even here.
I have limited knowledge of the strong force but are you saying that in a black hole, the strong force holds photons to photons, photons to electrons, electrons to electrons, and so on between all possible combinations of all things? I have never heard of any evidence of a universal force other than gravity and I don’t believe in that.
Don: not quite. I view a photon as little more than a bulge in space. IMHO in a black hole, the photons lose their individual identity. Like raindrops do when they fall into the sea. Like snowflakes do when they fall on Antarctica. After some time, those snowflakes are buried, and turn into ice. Think of the IceCube neutrino observatory. IMHO the same goes for electrons, which are merely photons in a closed path. So the black hole ends up being akin to one big spherical photon. A bulge in space, pressing outwards, creating the pressure gradient that we call a gravitational field.
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Now go back to thinking of space as an elastic medium. Then find a piece of elastic. stretch it, then let go. It snaps back. Because of a restoring force. If that wasn’t there, the elastic wouldn’t be elastic. And if space wasn’t elastic, waves wouldn’t run through it. The force is universal, but it isn’t like gravity. Somebody said something once about Kip Thorne being very interested in elasticity. I’m not sure why, but I think continuum mechanics does offer something important when it comes to fundamental physics. I think William Kingdon Clifford was essentially correct with his space theory of matter.
John lets back up for a moment. In fact, lets back out of the black hole. I would like to understand how gravity slows light, even before it reaches the event horizon. You have convinced me that there is a gravity gradient and it causes light to slow down as it descends in the gravity gradient. But what creates this gravity gradient that extends forever. I don’t understand how the stress-energy-momentum tensor creates gravity because you can put a thing in a heavy-duty shielding capsule and it still is affected by gravity as if the capsule was not there.
Don: please read
https://physicsdetective.com/the-speed-of-light/ and https://physicsdetective.com/how-gravity-works/. Here’s the important bits:
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The equation for the speed of a transverse seismic wave is given as csolid,s = √(G/ρ), where G is the shear modulus and ρ (rho) is the density. The equation for the speed of light in the vacuum of space is given as c = 1/√(ε0μ0) where ε0 is vacuum permittivity and μ0 is vacuum permeability. There’s a reciprocal because permittivity is a “how easy” measure rather than a “how hard” measure…
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For an analogy, imagine you have a block of gin-clear ghostly elastic jelly, with grid lines in it so you can see what’s going on. You slide a hypodermic needle into the centre of the block, and inject more jelly. This represents a concentration of energy bound up as the matter of a massive star. It creates a pressure gradient in the surrounding jelly. Stress is directional pressure, the pressure is outwards, and Einstein’s equation Gμν = 8πTμν is modelling the way gin-clear ghostly elastic space is conditioned by the energy you added. But don’t forget that you added jelly to represent energy, and that the jelly also represents space. Space doesn’t just have some kind of innate intrinsic vacuum energy. At some deep fundamental level, space and energy are the same thing.
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The heavy duty capsule is made of matter, matter is made of energy, and space and energy are the same thing. The stress-energy-momentum tensor is describing how a concentration of energy in the guise of a massive star creates a pressure gradient in the surrounding space. This alters the motion of light through space. Then because something like an electron is just light in a closed path, matter falls down. It’s like Einstein said: the contrast between ether and matter would fade away. He was saying the contrast between space and matter would fade away. Hence the capsule doesn’t shield against gravity.
John, I think we are getting closer to what exactly I don’t understand. What injects gravity into a heavy-duty capsule? Is gravity transported by a particle, wave, or the seeping of space? What is transported? Is it pressure, shear, momentum, momentum flux, energy? Obviously the outside pressure and sheer are not transported into the capsule.
Don: let’s start by asking what causes gravity in the space above a massive body. It’s the energy tied up as the energy of that massive body. I think you can understand it using this analogy: imagine you have a block of gin-clear ghostly elastic jelly, with grid lines in it so you can see what’s going on. You slide a hypodermic needle into the centre of the block, and inject more jelly. This represents a concentration of energy bound up as the matter of a massive star. It creates a pressure gradient in the surrounding jelly… So what is transported? Energy. This is why Einstein said “the energy of the gravitational field shall act gravitatively in the same way as any other kind of energy”.
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But note this: don’t forget that you added jelly to represent energy, and that the jelly also represents space. Space doesn’t just have some kind of innate intrinsic vacuum energy. At some deep fundamental level, space and energy are the same thing. So space is transported too. Now, do you remember people saying an atom is 99% empty space? That figure is wrong. The correct figure is 100%. So your capsule is made of matter, which is made of energy, and energy and space are the same thing. So the walls of your capsule are no barrier to the gravitational field that is in essence a pressure gradient in space. See does matter differ from vacuum? by Christoph Schiller. The answer is no. Also see https://physicsdetective.com/black-holes/ and https://physicsdetective.com/firewall/.
John, I am currently trudging my way through Christoph Schiller’s paper you suggested. I usually don’t make it past the opening synopsis of these top grade academic papers because I really can’t comprehend them. Way,way over my head. However I am going to do this one,slowly but surely, and already have questions coming soon. Until then stay healthy and enjoy your country’s relative tranquility.
Willco Greg. Maybe I should write about our “relative tranquility” here in the UK, and the associated propaganda and censorship that goes with it. Or maybe not. But I should re-read Christoph Schiller’s paper I suppose. I first read it in 2005 I think. I was just taking another look, and I noticed he referred to spacetime when he should have said space, and he said this on page3: “At these dimensions one observes relativistic quantum effects, such as particle-antiparticle creation and annihilation”. We don’t actually observe particles popping in and out of existence. It’s like what Rugh and Zinkernagel said: photons do not scatter on the vacuum fluctuations of QED. If they did, “astronomy based on the observation of electromagnetic light from distant astrophysical objects would be impossible”.
John, I firmly believe in the doctrine of “A man is king of his own castle “. You have a bully pulpit Sir, so why not use it! After all, suppression of scientific thought and information is as old as science itself : Galileo vs. The Pope; Einstein vs. Nazism; Oppenheimer vs. McCarthyism ; Trump/Johnson vs. the medical specialists; celebrity authors,journalists bloggers,academics,and finally scientists who put money,fame and power before truth. I’m sure the list is much longer.
I think I’ll stick to physics Greg. As for Trump vs the medical specialists, I heard that Tom Hanks was given chloroquine, and I’ve heard stories of other people benefitting from it. I don’t know if it’s true, but I note this 2005 paper Chloroquine is a potent inhibitor of SARS coronavirus infection and spread. There’s also the Guardian article Questions raised over hydroxychloroquine study which caused WHO to halt trials for Covid-19. The article makes it clear that somebody made up the numbers. It’s clear to me that the Lancet paper was a political hit job, which is why it’s now been withdrawn. And yet on the back of that, the World Health Organisation said hydroxychloroquine was so dangerous that they were stopping trials. Even though it’s a prescription drug. That is ugly. But it’s OK folks, there’s a new “Recovery” trial that tells you that hydroxychloroquine is no good. I’m afraid I don’t believe that this new trial was conducted fairly. Especially since somebody told me they only gave the hydroxychloroquine to people who were close to death. I am reminded of political surveys:
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Good Morning. I’d like you to conduct a survey for me please..
Certainly Sir! What result would you like?
I forgot to mention: I’ve been seeing reports that smokers are under-represented amongst coronavirus patients. Then ASH commissioned a study which said smoking makes coronavirus worse. As an ex-smoker with experience of non-smoker colleagues suffering more colds etc, I think smoking does offer some kind of protection against some ailments. Amazingly, tobacco used to prescribed by doctors. And I’m mistrustful of the ASH study.
Not only did they prescribe it, they literally blew it up your ass.
http://www.todayifoundout.com/index.php/2014/05/origin-expression-blow-smoke-ass/
Interesting John, it seems most of the claims about smokers you found doing research in the UK contradict most of the info here in the states. Over here when info comes from medical experts concerning the pandemic and how to combat it, I tend to agree with their recommendations. However when it comes to what medication(s) work and what would be best, I am extremely skeptical. Big Pharma controls everything over here, and each individual corporation would slice each others throats, sell their own mothers to the gypsies, and gladly feed us rat poison in order to make more profit.
It sounds like there are some issues in medicine, Greg. A colleague at work was telling me about his wife who was prescribed a succession of 11 different drugs, each of which caused some side-effect that needed yet another prescription. Something similar happened to my mother. I only found out when she started losing teeth, due to an arthritis drug that softens ligaments. Your teeth are held in by ligaments. Both are off all medication now. My own doctor seems very good, and says she prefers to take a “holistic” approach where possible. But I get the impression doctors are under constant pressure to prescribe. If you google that, you read about patient pressure, but I suspect there’s more pressure coming from drug companies to get patients onto expensive long-term preventative prescriptions.
Amen John ! Over prescribing due to illegal or barely legal cash kickbacks and unregulated pillmills is what started the prescription opioid epidemic in this country. Luckily over the last few years the politicians and law enforcement has drastically cracked down with such unscrupulous people. Along with the easy access to over the counter ingredients to cook meth.
Several years ago I had a simular experiance with my elderly father,luckily I had the presence of mind to ask his pharmacist to review all the new prescriptions written by new doctors. My father could have been poisoned by taking redundant amounts of meds. Since then there has been much needed progress on medical data bases coordinating doctors,pharmacies,and patients. But unfortunately many Americans don’t have access. I am NOT a socialist by any means, but our health care needs to be nationalized.
I have been not seriously religious since my mid-teen years,much more spiritual than devout; but I do firmly believe what a sage man once wrote : ” probaly the love of money is the root of all evil”.
I think the medical situation is getting worse Greg. There seems to be a push at the moment to claim that all older people have early onset diabetes requiring medication, and that all teenagers have mental issues requiring medication. I share your sentiment about US healthcare, and I’m not a socialist either. After recent events, I’m even less of one. LOL!
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Which reminds me, I really must put finish my article about censorship and propaganda and the erosion of free speech in physics. Sorry I haven’t posted much of late, the day job has been hard work recently..
what a sage man once wrote : ” probaly the love of money is the root of all evil”.
That is from the book of Timothy, verse 6, line 10. “For the love of money is the root of all evil:”
My corollary: “For the love of theory is the root of all folly”.
No worries Mate, thanks as always for the keen conversation. Until your next sterling article,everyone stay safe and healthy.
Pinball/compact = Bohr atom, discrete particles.
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If “space” is “real”, some kind of aether, then matter is some kind of relatively stationary node, a resonance or interference, in what is necessarily a cacophony of currents. Picture a pond in a rainstorm. It’s electrical all the way with the strong, weak, and gravitational forces being different resonant modes/interference patterns of the fundamental EMF. We see analogs of this in the behavior of plasmas. Plasma is very strange stuff. It’s so strange that after 50 years of trying to make the Tokamak work they’re still 15 years away.
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I have reluctantly come to think that Copenhagen is as good as it’s going to get. The many-minds interpretation removes some of the philosophical/psychological objections. The cat is not in some indeterminate state, it’s alive for Alice, dead for Bob, and as usual Bruce is out to lunch.
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The expanding universe: It is dependent on one observation, and one observation only – the Hubble red shift. When Hubble reported the red shift in 1929 many sought to explain it. The discussion settled on two propositions, the expansion of the universe as proposed by LeMaitre or “tired light” proposed by Zwicky. At the time the interstellar and intergalactic media were thought to be a true vacuum as defined by Einstein, thus LeMaitre’s view prevailed. Until recently we haven’t had any reason to change that view. Until recently.
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The radio astronomy of Pulsars reveals that in the leading edge of the pulse shorter wavelengths arrive before longer wavelengths. This time dispersion by wavelength is proportional to the distance to the Pulsar. This is behavior that is what is observed in a dense medium – a medium with an index of refraction greater than unity. Recent observations show the same behavior in “Fast Radio Bursts” originating in both our own and remote galaxies. No expansion. William of Ockham saddles up again.
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I don’t think of the atom as being made up of pinball things. I know the depictions show the electron as some little billiard-ball thing. But IMHO the electron’s field is what it is. It isn’t some point-particle thing that has a field, it is that field. Trying to feel for some hard little lump in the middle is as futile as searching for a hard little lump at the centre of a whorlpool.
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I think space is real, that a photon is a wave in space, and the electron is 511keV photon in a double loop “trivial knot” standing-wave configuration. Standing wave, standing field.
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I don’t share your views on the Copenhagen interpretation. I think it’s trash. You should read my historical articles on that, starting with the old quantum theory begins. Trust me Roy, the Copenhagen school were a bunch of quacks and charlatans.
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As for the expanding universe, I would think the universe was expanding even if there was no Hubble shift. Because space isn’t just like some kind of gin-clear ghostly elastic. It has pressure too. IMHO it’s like a stress ball when you open your hand. Can you give me a reference on those pulsars?
Test reply.
“It’s clear Hawking didn’t understand the first thing about gravity, and had never read what Einstein said. He was winging it, and getting an easy ride on account of the wheelchair.”
John, considering the abject failure of your Relativity+ and your continued failure, over the decade or so since then, to learn any actual working mathematics or physics, this comment of yours shows the bitterness you feel.
I’m not surprised you’ve had to make your own website, given every single respectable forum you ever joined either kicked you off or had your claims shredded by actual physicists. I put your name into Google to see if you were still wasting money self publishing your nonsense – I guess this is a cheaper option that gives more immediate gratification for delusions of grandeur.
Remember how you once told a few of us we’d be teaching your stuff in a few years? I guess that didn’t happen.
You obviously like to reference highly mathematical papers but you don’t actually go into the mathematics. Your “Because Einstein said [blah] then Penrose/Hawking must be wrong” isn’t backed up by anything other than …. your belief your superficial understanding of highly technical terms is somehow superior to a century of actual physicists? Why not write up your conclusions and get them published in a reputable journal? Why not play more than armchair detective and actually contribute to science? Why stay in your own little fiefdom of this website?
Write up your “disproof” of the work of Penrose & Hawking, based on your “understanding” of Einstein’s work, and submit it to a journal. Post the pre-print on this blog. Or Vixra (since ArXiv won’t let you). Tell us which journal you’re submitting to. And then tell us the feedback.
I’ll check back in a few weeks. See if you’re more than a decade of talk and self delusion.
Alphanumeric: I’m awfully sorry, your comment was in my spam folder. Since I’ve recently been talking about censorship. that’s a little embarrassing. I hope you didn’t think it was awaiting my approval, which I’d withheld. I don’t operate like that. I believe in free speech in science. Unfortunately as you know, others don’t, which is why even bona-fide professional physicists can’t get their important papers into a journal. So I don’t fancy my own chances there.
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As for Hawking, one of his major papers was “singularities and the geometry of spacetime. On page 76 he talked of “such a strong gravitational field that even the ‘outgoing’ light rays from it are dragged back”. It’s clear Hawking had never read Einstein’s fundamental ideas and methods of the theory of relativity. That’s where Einstein said a gravitational field is a place where “the speed of light is spatially variable”. So Hawking didn’t know that in a gravitational field, light speeds up as it ascends from floor to ceiling. He didn’t know that in a strong gravitational field, outgoing light rays aren’t dragged back. They speed up even more. This means just about Hawking ever said about gravity and black holes is wrong.
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How are you keeping anyway? I hope you are well!
Could black holes be connected to one another and to the beginning and end of time?
Instead of opening into another universe(s), why not this one?
I don’t think so Dan. As far as I can tell black holes are just the spatial equivalent of icebergs, that’s all. With nothing magical or mysterious about them. Of course, people love stuff like the wormholes and time travel peddled by the likes of Kip Thorne in Interstellar. But as far as I can tell, that’s on a par with saying a furnace door is the gateway to paradise. It’s “woo”, not physics.
Hello.
I saw the elephant paradox picture on your post, and I was about to post my own picture about how things really happen, when by pure chance I found this paper about “Planck Stars”:
https://arxiv.org/pdf/1401.6562.pdf
The idea is very similar to that of a frozen star, but it explains how it can evaporate nicely.
Of course, there’s no singularity, no event horizon, no elephant-at-two-places and no information loss paradox.
All there is are just two extremely different reference frames observing the same events, but one of them (the external observer) sees the Planck Star evolving in super slow-motion, because the events that take place inside the star are affected by extreme time dilation.
Inside the Planck Star, the gravitational pull is counteracted when the energy density reaches the QM vacuum density. Then, it bounces back.
From the Planck Star POV, everything seems to happen quickly.
But for an outside observer, the Planck Star appears to be frozen, because the time of the observer runs extremely quickly, compared to the proper time experienced near or inside the star.
From the paper:
“A black hole is essentially a collapsing and bouncing star that appears frozen because it is seen in slow motion.”
The paper is also extremely easy to read. I think it is really good stuff.
What do you think?
Hmmn, Carlo Rovelli. I’ll take a look. I have to go now I’m afraid, the wife is calling me for a glass of Malbec. But for now I wasn’t impressed by the “quantum gravitational” in the abstract. Or the Hawking radiation. Have you ever read any of Hawking’s papers on the subject? I have, and I was not impressed. But no matter, I’ll get back to you. Toodle pip!
QuantumWormholes: I copied the paper into a word document and made notes about it. Here’s what I think:
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Measuring the effects of the quantum nature of gravity is notoriously difficult because there are none.
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There’s no evidence of Hawking radiation, and no evidence of primordial black holes either.
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The information paradox is based on a total misunderstanding of gravity and black holes, and electromagnetism and QED. See my latest article on the black hole charlatans.
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The possibility of measuring a consequence of quantum gravity in cosmic rays is hypothesis on top of conjecture on top of speculation.
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Friedmann was an artilleryman. The Friedmann equation describes a cannonball universe, and is wrong. A gravitational field is a place where space is inhomogeneous. The FLRW metric assumes the homogeneity of space, which means no gravity.
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The speed of light varies with energy density, and must surely vary with the evolution of the universe too.
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Bouncing universes are yet more speculation.
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To study if and how quantum gravity could also resolve the r = 0 singularity at the center of a collapsed star? There is no r = 0 singularity, because a gravitational field is a place where there’s a gradient in the speed of light. At the event horizon the speed of light is zero, and it can’t go lower than that. So there’s no gravity there, and no further collapse. So whilst you might call it a “Planck star” or a “Gravastar” or a “BEC star” or something else, there’s no need for pressure to counter further collapse.
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Units where c = 1 are the wrong units, because at the event horizon c = 0. Not because time slows down. Because light slows down. Totally. That’s why the black hole is black.
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Eddington-Finkelstein coordinates use “tortoise” seconds that last forever. They’re junk coordinates invented by Penrose.
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Rovelli doesn’t know that electromagnetism is the strong curvature regime.
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The negative energy partner in a Hawking pair? There are no negative-energy particles.
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He doesn’t understand gamma ray bursts either. Matter falls faster and faster because the speed of light is getting slower and slower. That can’t continue without limit.
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All in all there’s a lot of speculation and abstraction in this paper. Rovelli tries to make it respectable with a heavy salting of smoke-and-mirror mathematics, but the foundations just aren’t there, and I’m afraid I thought it felt like wishful thinking. Sorry.
After seeing again the beautiful picture of the motion of stars around Sagittarius A*, I couldn’t help but notice how every single star is moving relative to a single, STATIONARY point.
Maybe it’s an artefact of the image, and there is an actual wobble on the frozen star; but this study https://arxiv.org/abs/0808.2870, which is quoted on wikipedia as the main source of the mass data, states that the BH radial velocity is consistent with… you guessed it right, zero. They also offer an updated mass to take this in consideration, as to make the center of mass of the whole system lie exactly at the center of the black hole. Occam’s razor would led me to believe this is an overfit, and to conclude that black holes don’t gravitate.
Leon, have you read this yet?
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https://physicsdetective.com/we-have-to-talk-about-ligo/
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As far as I can tell the mechanism by which gravity works is not present within a black hole. So whilst a black hole can cause gravity, IMHO it does not respond to it. For example, if a small black hole collided with the Earth, it would go straight through and carry on. It wouldn’t settle at the centre of the Earth and consume the planet.
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As for Sagittarius A*, I don’t know if the lack of any wobble is at all significant. That sucker is massive.
So I’ve been thinking about this frozen black hole idea you presented for a while now. I really like the idea that the black hole won’t be affected by gravity since c=0 (can’t accelerate when your top speed is 0), or that a black hole spinning at c, is actually spinning at 0 since c=0 at the horizon.
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Anyway, i was just reminded that gravity travels at the speed of light. So if you have a blackhole, how is the mass inside the black hole sending out gravity through the event horizon, where the speed that gravity would be traveling is zero.
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Perhaps there is some limiting physics that prevents the speed ever getting to zero that we don’t yet know. Sorta like how PV=nRT breaks down at high densities and you have to take into account the details of the molecule sizes, etc.
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Just my thoughts over my coffee this morning.
Doug: gravity isn’t being “sent out” per se. IMHO the way to look at it, is that space and energy are, at some fundamental level, the same thing. They’re like some kind of gin-clear ghostly elastic solid. So if I start with a homogeneous region of space, and then add a concentration of energy in the guise of a massive star, it’s like sliding a hypodermic needle into the gin-clear ghostly elastic solid, and injecting more of the same. This “pushes out” on the surrounding space, the effect diminishing with distance. Then you’ve got a region of inhomogeneous space. And that’s what Einstein said a gravitational field is. In this region, the speed of light varies, so light bends downwards like sonar waves bend downward in the sea – because the speed of sound reduces with depth. Then matter falls down because of the wave nature of matter, because an electron can be likened to light going round a closed path. The horizontal component bends downwards, so the electron falls down. If your concentration of energy is so concentrated that it’s in the guise of a black hole, it still “pushes out” on the surrounding space, the effect diminishing with distance. You still have a region of inhomogeneous space. You still have a gravitational field.
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I don’t think there’s some limiting physics that prevents the speed ever getting to zero. If there was, black holes would not be black. The upward vertical light beam speeds up. It has to have a speed of zero at the event horizon, or it would end up escaping.
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PS: I imagine a black hole reacts to gravity like a photon. But that means a black hole moving horizontally above the surface of the Earth would be deflected downwards by only a tiny amount.
Interesting,
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I’ve read your black hole essay and it was very convincing that the speed of that black hole photon is 0, so therefore a black hole cannot move at all. If these electrons in the black hole are going around in a closed path at speed 0, then they cannot react to gravity.
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Either way, there’s no evidence that black holes are black, every one we’ve detected is shining bright. So yes, I am suggesting they are not black and that perhaps a speed of 0 is not realizable, just a thought.
I’ve read your black hole essay and it was very convincing that the speed of that black hole photon is 0, so therefore a black hole cannot move at all.
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I don’t see it like that, Doug. I think of the original “frozen star” version of a black hole, then I think of a fish. The speed of a fish in water is maybe 5m/s. But if that fish is situated in frozen water, such as an iceberg, then the speed of that fish in that frozen water is 0m/s. But the iceberg can still move through the sea, because the sea isn’t frozen.
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If these electrons in the black hole are going around in a closed path at speed 0, then they cannot react to gravity.
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Quite. Which is problem for LIGO.
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Either way, there’s no evidence that black holes are black, every one we’ve detected is shining bright.
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Sagittarius A* isn’t. We can’t see it. Don’t forget that the Event Horizon Collaboration’s image is not an actual image. They didn’t capture an image. They captured data which was used to create an image. Don’t forget this: “There’s an infinite number of possible images that could have been created from the sparse measurements that we took”. The problem for me is that the images are consistent with Kerr black holes, which allow for time travel, which is science fiction.
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So yes, I am suggesting they are not black and that perhaps a speed of 0 is not realizable, just a thought.
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It’s possible I suppose. But again, I go back to my frozen star and the iceberg. That water is frozen, and the speed of that fish is 0.
So if the fish is frozen, how is gravity capable of making it curve. This goes against all your explanation of gravity curving matter because it’s a variation in light speed. If it’s frozen, both sides of the electron or photon are going at the same speed and therefore there is no longer the mechanism of gravity to change it’s path to due a speed variations.
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I assumed the black hole is now frozen into the rest frame of the cmb.
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Either way, Sagittarius A* was found because it’s an extremely bright radio source, check any reference, it’s well know that it is a very bright object.
The fish is a stand-in for a photon. The horizontally-moving photon curves downwards because there’s a vertical gradient in the speed of light. Its path curves like the path of your car curves when it encounters mud on the side of the road. But if the speed of light is zero, the photon isn’t moving at all, and there is no gradient in the speed of light. So the photon just sits there. Since the electron is akin to a photon going round in a closed path, both sides of the electron are indeed going at the same speed. But that speed is zero. So there is nothing to make the electron fall down.
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The moot point about Sagittarius A* is that we can’t see it in visible light. That sucker ain’t shining like the Sun.
PS: since an iceberg can spin, maybe a black hole can spin too.
Why wouldn’t a black hole spin, aren’t they still subject to tidal forces from the rest of the galaxy? Maybe it would much slower then, just like some planets rotate? Or even better, what if their insides moves, are configured like knot theories?🤔?
The way it’s normally described is that you start with a rotating star. As it collapses it gets smaller, and conservation of angular momentum means the rate of rotation increases. This is extrapolated such that at the black hole stage, the rotation speed is said to be circa half the speed of light.
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However a gravitational field is a place where the speed of light varies, such that at the event horizon the speed of light is zero. So the extrapolation does not work, because half of zero is zero. In addition gamma ray bursts indicate that an electron or proton falling into a black hole can not survive, and is broken down into photons and neutrinos. That means the angular momentum is dissipated, like what happens when a flywheel breaks up. The photons and neutrinos that are emitted downwards end up adding to the black hole mass, so the black hole still increases in size. But the mechanism by which angular momentum is normally conserved is not present.
It does make sense all of the incoming energy particles can’t all be broken down into a proton and neutron medium of some sort.(your black,dirty Bose-Einstein condensate snowball?). I agree with you and others that these leftovers (mostly photons and neutrinos) gets ricocheted back outside the event horizon which is what is probably doing all of spinning ,which in turns also drives the relavistic jets? Energy isn’t actually being destroyed at all, most is being stored,and the rest just being redirected? No parallel universes,no wormholes,no multi-dimensions , just pure energy doing what it does best: confuse the F out us.
I’m sure there’s rotation in the accretion disk, Greg, and there’s definitely something powering those relativistic jets. But as to the black hole itself spinning, it can’t be like they say. Especially if the Kerr black hole permits time travel, and wormholes to the parallel antiverse et cetera. That sort of thing is just pseudoscience. But sadly the popscience editors love that sort of stuff, and so do young kids who don’t know any better. They grow up being confused, when guys like Einstein had a much simpler and understandable view of this sort of stuff. He talked about matter and energy as being the same thing, and space and matter being the same thing too. So a black hole is just a lump of denser space in space, as it were. What’s not to like?