Black holes – THE PHYSICS DETECTIVE : censors me, Jim. I wonder why?

Note by Jim: I'm posting this page here, because John Duffield, who is a nice guy actually, and self-proclaimed "physics detective", censored my comments, despite claiming he's pro-free speech in science. Obviously, like most censors, he means he does not censor comments he agrees with, or thinks he can find a plausible refutation for. Scroll down to where I discuss relativity with Duffield, and then he censors me ("Post awaiting moderation"). But, try as he might to hide it, the truth will out! Who is correct, John, or me (Jim)? I will leave you to make up your own minds. To re-iterate, I post this here as a record of the whole truth. Also, as a gesture against censorship in science.
I have not included, here, the (long) article itself, as of July 05, 2021, written by Duffield (much of the contents of which, on that date, at least, I disagree with). I have included the comments between Duffield and me, including those comments that he decided to censor (scroll towards the bottom of the page).

This Post Has 66 Comments - NOTE: I, JE, deleted those comments before I joined in the discussion... - JE

  1. Harald

    Nice idea to describe a black hole as a hailstone, building up layer by layer. (I rather imagine a pavement covered by old chewing gums:-) When asking about the event horizon on PSE it is interesing to see how everyone goes a great length to confirm that the observer sees nothing special. Who bloody cares. If I look at my kitchen clock, my question is: did the observer reach the event horizon by now, will he tomorrow, will he in a gazillion years? And according to what I understand from the formulas, the answer is plain NO! Now if that observer does not reach the event horizon any time soon, how then is the matter going to collapse into a singularity any time soon?
    As you describe, the progression of time is not so much different from the progression of light. Measuring the speed of light by how long a beam of light takes to travel a meter using a clock that defines time by how long light takes to travel a meter, of course local measures of c are always the same. Again, who cares. According to my kitchen clock, neither light nor time can progress near the even horizon, so neither matter nor energy will progress; how should it collapse.
    What I wonder is, how the space behind the event horizon can be described when its like frozen. There are nice thought experiments here https://physics.stackexchange.com/q/304776/73067 and here https://physics.stackexchange.com/q/421036/73067 but the answers are depressingly similar in trying to explain that this is a short lived situation and much too complicated to describe today

    Maybe this singularity-business is much easier than commonly thought. In a certain way, space is like the trunk of your car: when its full, its full. There is no singularity in the middle of your luggage:-)

    1. Don

      Got it. Thanks John

    2. John Duffield aka “Farsight” wrote above :

      ” but either way there’s something very small and very massive at the heart of our galaxy. We’re confident of this because of many years of work by many good men and women.”
      .
      My scale-invariant quantum antigravity hypothesis is very simple and clear, and it naturally explains what this: ” something very small and very massive at the heart of our galaxy” actually is. And it happens to be something that also eliminates the need for dark matter.
      .
      Galaxy rotation is the arena where the so-called “strong gravity” dominates.
      .
      My hypothesis clearly explains the principle of how the “strong gravity” is being generated by normal galactic dynamics, and therefore this: “something very small and very massive at the heart of our galaxy” is not massive at all, because it is (small) geometric center of the “strong gravity” being generated by the galaxy.
      .
      How could “strong gravity”, or any gravity at all, be possibly generated without anything massive, like black hole, or dark matter?

      I have noticed that on this blog there have been some doubts expressed about the ultimate validity of mass-energy equivalence principle. Even if this principle is not as universal and unconditional as mainstream physics would like us to believe, for the sake of my argument I assume it to be good enough.
      .
      ” Even masses at rest have an energy inherent to them. You’ve learned about all types of energies, including mechanical energy, chemical energy, electrical energy, as well as kinetic energy. These are all energies inherent to moving or reacting objects, and these forms of energy can be used to do work, such as run an engine, power a light bulb, or grind grain into flour. But even plain, old, regular mass at rest has energy inherent to it: a tremendous amount of energy. This carries with it a tremendous implication: that gravitation, which works between any two masses in the Universe in Newton’s picture, should also work based off of energy, which is equivalent to mass.” — Dr. Ethan Siegel, Ph.D., Astrophysicist
      .
      So, how could “strong gravity”, or any gravity at all, be possibly generated without anything massive, like black hole, or dark matter?
      .
      According to my hypothesis, the “strong gravity” is being generated from energy generated by normal galactic dynamics. However, it is not just any energy, but a specific, well-known form of energy.
      .
      All the details are explained in my paper and on my website, and most importantly, my hypothesis is easily and cheaply experimentally testable on a table’s top.
      .

    3. Jim Eadon

      John, from the perspective of an outside observer, the concept of space and time breaks down inside the event horizon. So, it’s meaningless to talk about someone inside the event horizon shining a torch upwards. You’re extrapolating your spacetime experience on Earth with how things behave inside the event horizon.
      For example, an outside observer can never see anything enter a black hole, because, from an external perspective, anything falling into a black hole slows down to almost zero. Not quite, as, to get to zero would take eternity, it cannot happen, eternity is a limit forever out of reach. So, if nothing can go in, from the outside world, then nothing can be seen coming out of it.

    4. Jim Eadon

      As for 4-D spacetime, iight, unlike massive particles, travels in geodesics. From the point of view of a photon, that photon gets from A to B instantly, there is no concept of the passage of time at all.
      The Lorentz equations essentially a 4D spacetime fabric. Whereas Newton showed that the up-down dimenion is symmetric with left-right, forward-back, Einstein showed that the 4th dimension is symmetric with our 3D dimensions, except for a difference in sign.
      The 4D picture agrees with experiment perfectly. So, it’s a reasonable picture. Saying that the speed of light changes because time slows down is equivalent. Light takes longer, from an external observer, to get from A to B, due to travelling on a geodesic that is, relative to us, curved. So, unless you can determine an experiment showing which interpretation of the mathematics is physicsl, then it’s just a metaphical argument.

      1. Jim Eadon 30 Jun 2021 Reply
        ” So, unless you can determine an experiment showing which interpretation of the mathematics is physics, then it’s just a metaphical argument. ”
        .
        That is what I have always been saying to the likes of Dr. Jack Sarfatti :
        Mathematics is not physics.
        And mathematical physics is not experimental physics.
        .
        But the likes of Dr. Jack Sarfatti prefer to live in such a La-La Universe,
        where all of the above is one and the same.
        .
        .

      2. the physics detective

        Jim: but it isn’t meaningless to extrapolate the upward light beam to a smaller denser body, until you get to a point where the light doesn’t get out. This isn’t meaningless either: “the curvature of light rays occurs only in spaces where the speed of light is spatially variable”. Nor is this: “This means that a clock kept at this place would go at the rate zero”. The same applies to the upward light beam. Its speed is zero, that’s why the black hole is black. Why do you think its black? Because gravity pulls the ascending light beam down? That’s wrong. In a gravitational field, the upward light beam speeds up.
        .
        Re the outside observer never seeing anything entering the black hole, no problem. See what Einstein said about light rays taking an infinitely long time to reach what we call the event horizon. That’s because at the event horizon, the speed of light is zero. Simple. However black holes do exist, so see my hailstone analogy. A water molecule can alight on the surface of the hailstone, but it can’t pass through the surface. However it can be surrounded and buried by other water molecules, so the surface can pass through it. That’s what the frozen-star black hole is all about.
        .
        As for 4-D spacetime, it models space at all times. So there is no motion in spacetime. So light doesn’t travel on a geodesics through spacetime. Yes, you can model the motion of light through space using spacetime, but make no mistake, the motion is through space, not spacetime, and the photon doesn’t get from A to B instantly. The 4D picture might agree with experiment perfectly, but the map is not the territory. Hard scientific evidence shows us that optical clocks go slower when they’re lower. So it’s not some metaphysical distinction. It cuts to the very heart of understanding Einstein’s general relativity, and why light curves – because space is inhomogeneous, wherein the speed of light is spatially variable. Saying light curves because it travels on a curved path through spacetime is throwing away that understanding and replacing it with a handwaving non-explanation that’s wrong on multiple counts, because there is no motion through spacetime, and spacetime curvature relates to the tidal force, not the “force” of gravity.

        1. Jim Eadon

          “Jim: … The same applies to the upward light beam. Its speed is zero, that’s why the black hole is black. Why do you think its black? Because gravity pulls the ascending light beam down? That’s wrong. In a gravitational field, the upward light beam speeds up.”

          John, let me explain the “upward”-pointing lightbeam inside a black hole. Inside the black hole, the gravitational field is so intense that there is no geodesic (in this case, a geodesic being the shortest distance between two points in a “curved” 4D space-time) that light can follow that extends beyond the event horizon.
          This explanation confounds our intuiton if you’re thinking in terms of our 3D-space experience, because, in our 3D experience shining a torch creates a beam in a straight line: the geodesic our intuition expects (the curvature of space is locally flat). In a black hole space is severely warped in 4D. If you’re not thinking in curved 4D, then you’re going to get extremely confused. Non-euclidian geometry is weird. Non-euclidian 4D geometry is even weirder.

          “Re the outside observer never seeing anything entering the black hole, no problem. See what Einstein said about light rays taking an infinitely long time to reach what we call the event horizon. That’s because at the event horizon, the speed of light is zero.”

          Be VERY careful before saying that. You’re getting yourself into all kinds of trouble. In the reference frame of someone crossing the event horizon, they see all light travelling at speed C. There is NO frame of reference where C is measured as equal to zero that can be experienced with finite energy, not unless you are a massless particle anyway. C is ALWAYS, and I mean ALWAYS measured as C.

          “Simple. However black holes do exist, so see my hailstone analogy. A water molecule can alight on the surface of the hailstone, but it can’t pass through the surface. However it can be surrounded and buried by other water molecules, so the surface can pass through it. That’s what the frozen-star black hole is all about.”

          John, that’s “simple”. And WRONG. The only reference frame where a “frozen-star black hole can exist, is the reference frame of an outside observer. In that referene frame, one sees matter falling towards, but never actualy into, the black hole.

          “As for 4-D spacetime, it models space at all times. So there is no motion in spacetime. So light doesn’t travel on a geodesics through spacetime.”

          A geodesic is the path, in 4D, taken by photons.

          “Yes, you can model the motion of light through space using spacetime, but make no mistake, the motion is through space, not spacetime, and the photon doesn’t get from A to B instantly.”

          Actually, from the reference frame of the photon itself, it does get from A to B instantly.

          “Hard scientific evidence shows us that optical clocks go slower when they’re lower. So it’s not some metaphysical distinction.”

          Yes it is.

          “It cuts to the very heart of understanding Einstein’s general relativity, and why light curves – because space is inhomogeneous, wherein the speed of light is spatially variable.”
          To get that to work, you need “speed of time” to “slow down” – ugly! Also, it’s just philosophy. You’re just trying to interpret the equations in one way, instead of another, more natural, way. You’re trying to bend spacetime by bending it in the “time” axis. Worse, you can give me no experiment that can show that what you are saying is even meaningful as physics.

          “Saying light curves because it travels on a curved path through spacetime is throwing away that understanding and replacing it with a handwaving non-explanation that’s wrong on multiple counts, because there is no motion through spacetime, and spacetime curvature relates to the tidal force, not the “force” of gravity.”

          John, this is hypocrisy, a hypocritical philosophy. You’re just bending spacetime in the time-direction, then claiming that it means C varies. Which is just a handwaving non-explanation. You’re just a philosopher trying to mash up the GR equations in one way instead of in another way. The thing is, you make erronous statements about black holes and “time stopping” along the way, which is a red flag.

        2. Jim Eadon

          An analogy.
          Let’s say you’re in “flat land”. You’re a 2D flat person, and and you’re in a black hole, the event horizon of which is a flat circle. You are inside that circle in the x-y plane. You shine a torch “upwards” to the “top” of the circle, along the y-axis, the circle being the event horizon. You see the light move away from you in a straight line – at first. It moves up the y-axis towards the boundary circle. But then what happens is, the light goes into the z-axis, and, in the z-axis, it curves away from your flat-land. Ultimately it goes around until, relative to the y-axis, it starts to go “backwards”. You do not see the z-plane, so, to you, the light goes up in the y-axis, then down again, in the y-axis.
          It’s as if the light is following a geodesic like the circumpherence of another circle, in the y-z plane, that arcs out of your flat x-y land. The z-dimension is curved, which is why the light moves in a circle relative to the flat-land.
          This is what 4D does to 3D inside a black hole event horizon. It can move a beam of light away from the event horizon, because it’s following a “straight line” in a curved 4D space. All straight lines curve away from the event horizon. Because curved space bends lines that are still the shortest distance between two points.

          1. the physics detective

            Jim, that is abject handwaving. Let me reiterate: there is no motion in spacetime. Light does not move in 4D spacetime. Google on there is no motion in spacetime. Your “explanation” is popscience nonsense that flatly contradicts Einstein’s general relativity. Here’s what Einstein said: “As a simple geometric consideration shows, the curvature of light rays occurs only in spaces where the speed of light is spatially variable”. He also said “This means that a clock kept at this place would go at the rate zero. Further it is easy to show that both light rays and material particles take an infinitely long time (measured in “coordinate time”) in order to reach the point r = μ/2”. You’ve already said this:
            .
            “For example, an outside observer can never see anything enter a black hole, because, from an external perspective, anything falling into a black hole slows down to almost zero. Not quite, as, to get to zero would take eternity, it cannot happen, eternity is a limit forever out of reach. So, if nothing can go in, from the outside world, then nothing can be seen coming out of it.”.
            .
            That nearly matches what Einstein said. But now you’ve totally changed tack, and you’re flatly contradicting Einstein. That means the general relativity you think you know isn’t general relativity. Which isn’t surprising, since it’s peddled by the likes of Kip Thorne, who will tell you that a black hole is a time-machine tesseract wormhole that leads back to your bookcase.

    5. Jim Eadon

      “a metaphical argument.”
      *metaphysical.
      Furthermore, the idea of time slowing down is not all that satisfying anyway. We know that the 3D world is spacial, and we know that time seems dimension like, so we’re dealing with a 4D world, where any point at any moment is described by 4 coordinates. To discuss that 4D world as containing curvature, similar to the curvature of the surface of the world, is, to me, more satisfying than the rather awkward explanation of “time slowing down”. How many seconds per second is time slowing down? At what rate is time “running” anyway?

      1. Jim Eadon 30 Jun 2021 Reply
        ” At what rate is time “running” anyway? ”
        .
        In GTR, “time” is the 4th stationary dimension of stationary space.
        This being the only reason why in GTR you can travel in time,
        in theory only, of course. Exactly, like Dr. Jack Sarfatti does it
        in his pseudo-scientific theoretical propaganda videos.
        .
        .

      2. the physics detective

        I didn’t say time slows down. I said light slows down. It’s that simple. Don’t overthink it. Read my article on the nature of time. Time is merely a cumulative measure of local motion. It isn’t something you can move through. Once you know this, you know that when Kip Thorne waxes lyrical about time travel, he is talking out of his arse. You might find it satisfying to think that gravity is due to a 4D world containing curvature, but you shouldn’t, because you’re confusing the abstract mathematical model with reality. We live in a world of space and motion. Not in some 4D block universe comprised of space at all times. Which is therefore totally static. Google on there is no motion in spacetime.

        1. Jim Eadon

          C is constant, so, therefore “time” must be warped (“slowed down” to slow down “C”. The reason? Any observer measuring C always measures it as exactly C.

          1. No, c is not constant. Optical clocks go slower when they’re lower. Because light goes slower when it’s lower. Just like Einstein said:
            .
            1912: “On the other hand I am of the view that the principle of the constancy of the velocity of light can be maintained only insofar as one restricts oneself to spatio-temporal regions of constant gravitational potential”.
            .
            1913: “I arrived at the result that the velocity of light is not to be regarded as independent of the gravitational potential. Thus the principle of the constancy of the velocity of light is incompatible with the equivalence hypothesis”.
            .
            1914: “In the case where we drop the postulate of the constancy of the velocity of light, there exists, a priori, no privileged coordinate systems.”
            .
            1915: “the writer of these lines is of the opinion that the theory of relativity is still in need of generalization, in the sense that the principle of the constancy of the velocity of light is to be abandoned”.
            .
            1916: “In the second place our result shows that, according to the general theory of relativity, the law of the constancy of the velocity of light in vacuo, which constitutes one of the two fundamental assumptions in the special theory of relativity and to which we have already frequently referred, cannot claim any unlimited validity”.
            .
            1920: “Second, this consequence shows that the law of the constancy of the speed of light no longer holds, according to the general theory of relativity, in spaces that have gravitational fields. As a simple geometric consideration shows, the curvature of light rays occurs only in spaces where the speed of light is spatially variable”.

            .
            As I’ve said before, what you’ve been taught flatly contradicts Einstein, so it isn’t general relativity. An observer always measures the local speed of light to be the same because he uses the local motion of light to define his metres and his seconds. Then he uses them to measure the local motion of light. Duh! That’s the tautology. I talked about it in https://physicsdetective.com/the-speed-of-light/, see https://arxiv.org/abs/0705.4507.

    6. Jim Eadon

      In fact, with time being a coordinate, the concept of time “slowing down” – (which is tautological, you measure how much something slows down using time) would lead to a “curved” spacetime anyway, in terms of how you would describe any point in physical space at any moment, and plot such points. So, back to square one.
      If you’re going to play god, and say Einstein was right about this, but wrong about that, prove it. Go ahead and prove it with a mathematical law of physics that contradicts the Einstein equations. Otherwise, it’s just blah blah blah, much ado about nothing. You’re not doing physics, you’re doing philosophy.

      1. the physics detective

        Jim: the evidence proved it. Irwin Shapiro used that evidence to prove it. See Wikipedia and take note of this: “Because, according to the general theory, the speed of a light wave depends on the strength of the gravitational potential along its path…” So the theory you were taught, which says the speed of a light wave doesn’t depend on gravitational potential, is not general relativity. By the way, I referred to Irwin Shapiro in the article above. You haven’t even read this article, have you? Have you read any of them?. Methinks the answer is no, because you think you know better. So much so that you haven’t even looked at the Einstein digital papers. It’s called hubris, Jim. Intellectual arrogance. I am reminded of the quote from Avatar: “It is hard to fill a cup that is already full”. I am also reminded of Alexander Unzicker, who said we should stop all physics funding, because it’s getting in the way of scientific progress.

        1. Jim Eadon

          Jim: the evidence proved it. Irwin Shapiro used that evidence to prove it. See Wikipedia and take note of this: “Because, according to the general theory, the speed of a light wave depends on the strength of the gravitational potential along its path…”
          John, this depends on reference frame. Also, in addition, light “slows” in any material or energy field, because the photons are being destroyed, and recreated by that material / energy field. The photons themselves are ALWAYS moving at exactly C. You fail to make this distinction, and so you make sloppy statements that are misleading.

          “So the theory you were taught, which says the speed of a light wave doesn’t depend on gravitational potential, is not general relativity.”
          See my comment above.

          “By the way, I referred to Irwin Shapiro in the article above. You haven’t even read this article, have you? Have you read any of them?”
          John, I have a degree in this stuff. You don’t.

          “Methinks the answer is no, because you think you know better.”
          No I do not, you’re attacking a strawman. Again refer to my comment above.

          “So much so that you haven’t even looked at the Einstein digital papers. It’s called hubris, Jim. Intellectual arrogance.”

          Ha ha ha oh the irony! How self-unaware is our physics “detective”. John, once you stop saying imprecise, misleading or worse, statements about GR, THEN you can lecture me. Please learn the difference between the “speed of a light beam travelling through a medium, vs what C is. This is fundamental stuff, and you conflate the two, like uneducated amateurs are wont to do.

          1. the physics detective

            No, it doesn’t depend on the reference frame. Because a reference frame is an abstract thing that doesn’t actually exist. I can point up to the clear night sky and show you the Moon, or a star, or a laser beam. But you cannot show me a reference frame. Do not elevate abstract mathematical concepts that do not exist, above the things that do. Space exists, and light exists, as does the motion of that light through space. But a reference frame does not. It’s like what I was saying about spacetime: the map is not the territory.
            .
            No, photons are not being destroyed as they move through space. You are winging it again, and making up hand-waving fairy tales to fit your conviction, which doesn’t match the hard scientific evidence. See my previous comment. Photons move slower when they’re lower. Just like Shapiro proved. Just like Einstein said. Repeatedly, year after year after year: the curvature of light rays occurs only in spaces where the speed of light is spatially variable. When it comes to general relativity, you think you know better than Shapiro and Einstein, don’t you? I’ve got news for you: you don’t.
            .
            As for I have a degree in this stuff, I’ve spent far far longer researching this “stuff” than you. And I’ve got it from the horse’s mouth. Not third-hand parrot-fashion in some academic madrasa from some quack who contradicts Einstein whilst peddling nonsense about worm holes and time travel back to your book case. I’m not just some uneducated amateur. Because I’m with Einstein and the evidence, and you’re not. Sorry Jim, but when it comes to GR, your “education” is miseducation. Take a look at Misconceptions in gravitational physics to understand just how wrong your education is. Then do yourself a favour. Stand in front of your bathroom mirror, and repeat after me: “Everything I think I know about general relativity flatly contradicts Einstein and the evidence, and therefore is flat out wrong”. The penny will drop eventually, and you’ll be a better man for it. Then you will understand this: Do your own research and think for yourself.

            1. Jim Eadon

              JD “No, it doesn’t depend on the reference frame. Because a reference frame is an abstract thing that doesn’t actually exist. I can point up to the clear night sky and show you the Moon, or a star, or a laser beam. But you cannot show me a reference frame. Do not elevate abstract mathematical concepts that do not exist, above the things that do. Space exists, and light exists, as does the motion of that light through space. But a reference frame does not. It’s like what I was saying about spacetime: the map is not the territory.”

              John, a reference frame is as “real” (this question is sounding like metaphysics, not physics) as any other aspect of the equations (“space”, “light” or whatever). Loosely speaking, It’s the state of the observer. If you do not know the state of the observer, then you cannot solve the equations regarding what is seen (or not seen) for typical physics problems. Because the equations give different answers for different observers, depending on their location and velocity (SR) and the local gravitational field and accelleration (GR).

              JD “No, photons are not being destroyed as they move through space. You are winging it again, and making up hand-waving fairy tales to fit your conviction, which doesn’t match the hard scientific evidence.”

              John, are you actually claiming that the Dirac Equation, and the standard model (a Quantum Field Theory) are wrong? Fascinating, gtiven they describe experiments to more than a dozen decimal places. I hope you have a proof of your wild claim, and win a nobel prize. There’s only one fellow “winging it” here, and it’s the guy without a physics degree.

              JD “Photons move slower when they’re lower. Just like Shapiro proved.”
              WRONG. Photons actually move at C. What is really happening is, a beam of light moves more slowly through an energy field than through a vaccuum. (In a pure, energy-field-free vaccume, there is nothing to absorb and re-emmit photons). But photons always move at the constant “C”. The slow-down of beam of light is entirely due to field interactions destroying, and, after a delay, re-emmitting photons. When the light arrives after passing through a medium or field, it’s not the same photons coming out as went in. See Dirac’s equation for details. I take your Einstein and raise you Dirac.

              JD “Just like Einstein said. Repeatedly, year after year after year: the curvature of light rays”
              John, see my comment about photons being absorbed and re-emmitted by energy and matter fields.

              JD “When it comes to general relativity, you think you know better than Shapiro and Einstein, don’t you? I’ve got news for you: you don’t.”
              John, you’re so high and mighty, aren’t you? Well, “detective”, I’ve got news for you. Your mistake is in interpreting what these men are saying about the equations. Observe ANY individual photon, and you’ll see it moving at C, the constant that is the speed of light in a vaccuum. Individual photons cannot “slow down”. Massless particles must move at C. Again, consider the reference frame, this time, of the photon. From such a reference frame, time does not exist at all. So, it cannot “slow down”, or you just gave it mass in effect. Which is impossible, at least for known physics.

              JD “As for I have a degree in this stuff, I’ve spent far far longer researching this “stuff” than you”
              John, the problem with this is, you do not have the correct scientific training to make sense of the equations. You’re just reading words, which are imperfect descriptions of the equations. And then you add 2 and 2 and declare it’s 3, because the 2’s “slow down”. Not so, because “2” is a constant.

              “I’m not just some uneducated amateur. Because I’m with Einstein and the evidence, and you’re not. Sorry Jim, but when it comes to GR, your “education” is miseducation. Take a look at Misconceptions in gravitational physics to understand just how wrong your education is. Then do yourself a favour. Stand in front of your bathroom mirror, and repeat after me: “Everything I think I know about general relativity flatly contradicts Einstein and the evidence, and therefore is flat out wrong”. The penny will drop eventually, and you’ll be a better man for it. Then you will understand this: Do your own research and think for yourself.”

              John, that’s a self-indulgent fantasy of the physics-uneducated amateur. You have no physics degree, you should show more humility, you’re inexpert.
              In conclusion, let me say that you are using language in imprecise ways, and consequently, you’re making incorrect statements about the science by pushing things too far, mixing up different concepts, ignoring fundamental entities, such as reference frames, etc. You make claims like “a reference frame does not exist”. That’s a red flag right there! You throw reference frames in the bin, when “reference frames” are the heart, the “relativity” in SR and GR. When such garbage is written, and that is only one various bizarre examples, then one can rest assured that the writer does not understand the even the basic basics of SR and GR. This is an simply a salient case of Dunning Kruger syndrome.

              1. Jim: no, a reference frame is not real. Nor is a world line, nor is a light cone. Whilst you might say that a reference frame is “the state of the observer”, that doesn’t change what’s there. For example, a black hole is a place where the speed of light is zero. That’s why it’s black. If you put an observer at that location, the speed of light is still zero at that location. It doesn’t change to 299,792,458 m/s. You might claim that “in his reference frame” that observer sees the speed of light at that location to be 299,792,458 m/s. He doesn’t. It’s a schoolboy error to think he does. The speed of light at that location is zero. So he sees nothing. Ever.
                .
                Re: John, are you actually claiming that the Dirac Equation, and the standard model (a Quantum Field Theory) are wrong? Fascinating, given they describe experiments to more than a dozen decimal places. I hope you have a proof of your wild claim, and win a Nobel prize. There’s only one fellow “winging it” here, and it’s the guy without a physics degree. I’m not winging it. Photons are not being destroyed and recreated as they move through space. See the black hole charlatans where you can read Svend Rugh and Henrik Zinkernagel’s 2002 paper on the quantum vacuum and the cosmological constant problem. They point out that photons do not scatter on the vacuum fluctuations of QED, saying that if they did, “astronomy based on the observation of electromagnetic light from distant astrophysical objects would be impossible”. Hence the QED vacuum energy concept is “an artefact of the formalism with no physical existence independent of material systems” Also read Something is rotten in the state of QED. Oliver Consa has investigated the claims that QED is the most accurate theory ever, and tells of theoreticians constantly changed their “predictions” to match experimental results. it’s scientific fraud, Jim. Sorry.
                .
                Re WRONG. Photons actually move at C. What is really happening is, a beam of light moves more slowly through an energy field than through a vaccuum. (In a pure, energy-field-free vacuum, there is nothing to absorb and re-emit photons). But photons always move at the constant “C”. The slow-down of beam of light is entirely due to field interactions destroying, and, after a delay, re-emitting photons. This simply isn’t true. You’re making things up to cling to conviction, and you’re contradicting Einstein, Shapiro, and the hard scientific evidence.
                .
                Re: John, you’re so high and mighty, aren’t you? Well, “detective”, I’ve got news for you. Your mistake is in interpreting what these men are saying about the equations. Observe ANY individual photon, and you’ll see it moving at C, the constant that is the speed of light in a vacuum. Individual photons cannot “slow down”. Massless particles must move at C. Again, consider the reference frame, this time, of the photon. From such a reference frame, time does not exist at all. So, it cannot “slow down”, or you just gave it mass in effect. Which is impossible, at least for known physics. As above. There is no way to misinterpret “the speed of light is spatially variable” or “the speed of a light wave depends on the strength of the gravitational potential”.
                .
                Re: John, the problem with this is, you do not have the correct scientific training to make sense of the equations. You’re just reading words, which are imperfect descriptions of the equations. And then you add 2 and 2 and declare it’s 3, because the 2’s “slow down”. Not so, because “2” is a constant. Your arrogance knows no bounds. I’m not the only one saying this. See The Speed of Light Everywhere the Same? by PhysicsFAQ editor Don Koks. The answer is no. Note this: “light speeds up as it ascends from floor to ceiling, and it slows down as it descends from ceiling to floor; it’s not like a ball that slows on the way up and goes faster on the way down. Light travels faster near the ceiling than near the floor. But where you are, you always measure it to travel at c; no matter where you place yourself, the mechanism that runs the clock you’re using to measure the light’s speed will speed up or slow down precisely in step with what the light is doing. If you’re fixed to the ceiling, you measure light that is right next to you to travel at c. And if you’re fixed to the floor, you measure light that is right next to you to travel at c. But if you are on the floor, you maintain that light travels faster than c near the ceiling. And if you’re on the ceiling, you maintain that light travels slower than c near the floor.”
                .
                Re: John, that’s a self-indulgent fantasy of the physics-uneducated amateur. You have no physics degree, you should show more humility, you’re inexpert. I know far more about this subject than you. I’m not showing humility to some guy who peddles the Kip Thorne pseudoscience that flatly contradicts Einstein, Shapiro, and the hard scientific evidence.
                .
                Re: In conclusion, let me say that you are using language in imprecise ways, and consequently, you’re making incorrect statements about the science by pushing things too far, mixing up different concepts, ignoring fundamental entities, such as reference frames, etc. It all starts with understanding one simple little thing. Here’s those quotes again: “the speed of light is spatially variable” or “the speed of a light wave depends on the strength of the gravitational potential”.
                .
                Re: You make claims like “a reference frame does not exist”. It doesn’t. That’s why you can’t show me one. It isn’t a fundamental entity at all. It’s a mathematical abstraction.
                .
                Re: That’s a red flag right there! You throw reference frames in the bin, when “reference frames” are the heart, the “relativity” in SR and GR. When such garbage is written, and that is only one various bizarre examples, then one can rest assured that the writer does not understand the even the basic basics of SR and GR. This is an simply a salient case of Dunning] Kruger syndrome. No it isn’t. Because I’m with Einstein, whilst you are not.
                .
                Edit 04/07/2021: Jim, whilst I’m all for free speech in science, you have overstepped the mark, and I have removed your latest abusive comments. End of conversation.

                1. Jim Eadon

                  Your comment is awaiting moderation.[Due to censorship - JE]

                  JD – “Jim: no, a reference frame is not real. Nor is a world line, nor is a light cone. Whilst you might say that a reference frame is “the state of the observer”, that doesn’t change what’s there.”

                  John, Regarding reference frames, if you are saying that the states of the observer, which I described, are not real, then you’re wrong. Observers have properties, attributes and states that are fundamental to SR and GR calculations. As I say, you do not even have a basic understanding.

                  JD “For example, a black hole is a place where the speed of light is zero.”
                  WRONG. Refer to my previous answers on this, I’m not going to repeat myself.

                  JD “That’s why it’s black.”
                  That does not explain why they are “black”, and, besides, blackholes do emit radiation, if Hawking’s theory is correct.

                  JD “If you put an observer at that location, the speed of light is still zero at that location.”
                  See my previous refutaiton to this myth.

                  “Photons are not being destroyed and recreated as they move through space.”
                  Yes, they are. I refer you to my previous explanation.

                  JD “See the black hole charlatans where you can read Svend Rugh and Henrik Zinkernagel’s 2002 paper on the quantum vacuum and the cosmological constant problem. They point out that photons do not scatter on the vacuum fluctuations of QED, saying that if they did, “astronomy based on the observation of electromagnetic light from distant astrophysical objects would be impossible”.
                  John, that a huge red herring. The cosmological constant problem is nothing to do with it. The CC is non-zero, and therefore photon absorbion and re-emmision occurs, obeying the Dirac equation.

                  “Hence the QED vacuum energy concept is “an artefact of the formalism with no physical existence independent of material systems” Also read Something is rotten in the state of QED. Oliver Consa has investigated the claims that QED is the most accurate theory ever, and tells of theoreticians constantly changed their “predictions” to match experimental results. it’s scientific fraud Jim Sorry.”
                  John, this is, shall we say, iffy. I’ve never heard of anyone in science is discussing the the issue this guy has raised. Red herring, red flag. In general, phycists surmise that QM is more fundamental than Relativity, and, they believe that Relativity is an approximation to a quantum field theory (quantum gravity).

                  JD “You’re making it up, you’re clutching at straws to cling to conviction, and you’re contradicting Einstein, Shapiro, and the hard scientific evidence.”

                  John,. that’s a nice bit of projection of your own faults. I’m not contradicting Einstein, nor Shapiro. I’m simply explaining them to you, who misunderstands the science, and says bullshit nonsense about it.

                  “There is no way to misinterpret “the speed of light is spatially variable” or “the speed of a light wave depends on the strength of the gravitational potential”.
                  Again, you confuse the speed of light through a medium with the constant “C”. No matter how often I point this out, you still get confused about it.

                  “No it isn’t. Because I’m with Einstein, whilst you are not.”
                  Keep kidding yourself. You’re an uneducated fellow, with zero scientific training, who cannot eventell the difference between the “speed of light” through a medium, such as an energy field, such as a gravitational field, or even the quantum vaccuum energy, and the constant “C” from E=MC^2. Seriously John, you are simply embarrassing yourself with your schoolboy errors. Many of which I have pointed out. You’re one of those men who thinks he understand modern physics using his intuition, instead of understanding the mathematics. Bad mistake.

                2. Jim Eadon

                  Your comment is awaiting moderation. [Due to censorship - JE]

                  I would like to make one more remark about the Einstein equations. For certain inputs, the equations give absurd answers. One of those absurd answers is the “singularity”, where matter is infinitely dense, squashed into a mathematical point. Physicists believe that this does not really happen. That, a new theory, quantum gravity, as yet undiscovered, will take over before that happens, showing that the singularity would not come into physical existence.
                  On a more subtle level, the “time stops here” solution to the GR equations also makes no physical sense. You cannot stop a massless boson, it’s as simple as that. To the physically and mathematically naive amateur, they see nothing wrong with that, when they should. So, how do we understand the Time-Stops solution? The answer is, you have to consider it a “limit”, analogous to considering infinities in calculus as “limits”, not actual (because the mathematics breaks down for calculus at infinity).
                  OK, so Time Stops is a limit. Next we turn to reference frames. From the POV of someone falling into the black hole, then time never stops, even though they cross the event horizon. That’s what the equations say. It’s only for an outside observer that the GR equations say Time can be zero. But, again, this is a limit, and it’s not physical. It NEVER happens. Photons always travel at C. As I explained before, from the outside reference frame. one sees matter approaching the event horizon, but NEVER reaching it. To get to the time stops limit, you would have to observe what happens for ETERNITY. (Besides, quantum graviational effects would probably prevent time “stopping” even then!).
                  So, John, your approach to GR is mathematically and physically naive. Beware using your layman’s intuition when it comes to modern physics!

      1. Jim Eadon

        Hi Ziggy,
        I wasn’t particularly denigrating philosophy. Einstein was a philosopher about Quantum Mechanics, but it turned out that Quantum Mechanics did not like his philosophy. Not one bit…
        And that’s the problem for philosophy. 3000 years of thinkers failed to predict quantum mechanics. Newton was way ahead of his time, when science was “natural philosophy”, he practically invented physics.
        Clifford, a British mathematician (inventor of the important Clifford Algebra), anticipated relativity about 30 years(?) before Einstein, describing how he thought cosmological physics would evolve along geometric lines. He was precient. Lorentz invented the mathematical equation of special relativity (a non-euclidian geometry basically) but failed to apply it to the real world, and become a celeb.
        Those are the great thinkers of history, guys like that.