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rjbeery

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Everything posted by rjbeery

  1. I have personally never heard of gravitational time dilation being explained via "width contraction" to maintain the global invariance of c, but I guess that would work. Varying absorption/emission times does not work. As an aside, I saw an interesting video about radiometers which claimed that the rotation comes from the edge of the fans. The face color of the fans does not matter, which makes sense if you think about it -- the energy hitting each side of the fan is the same, and the energy being emitted from the black side is the same as the energy being reflected from the white side.
  2. Clock A and clock B are in relative motion. A claims that B is clocking slowly, while B claims that A is clocking slowly. Observer C might claim that A or B are clocking more slowly, depending on his frame. All results are relative here. Now, clock A is beneath clock B in a gravity well. A claims that B is clocking quickly, while B claims that A is clocking slowly. Observer C agrees with A and B that A is clocking more slowly than B, regardless of his frame of reference. The time dilation differential between A and B here is absolute. I'm talking about the specific A-to-B comparison at their established locations. I don't want this discussion to take semantic detours so I'll gladly use something other than "absolute", but it must be a synonym for "absolute" because "relative" does not apply. That literally leads to a logical contradiction, which I mentioned earlier. The so-called 'radiation pressure' would have to vary by the distance the photon traveled in order for the illusion to be maintained. The re-emission time would have to be delayed by a fraction-of-a-second up to many years, depending on the future path of the emitted photon. A remote variance of c does not suffer that problem. I understand this but...I'm not sure this is a scalar field theory, is it? Just as light isn't refracted within a homogeneous medium, gravitational attraction would not manifest for masses in a homogeneous time dilation field. It's the gradient (i.e. the derivative) that determines the gravitational attraction, and a single point doesn't hold enough information. I appreciate that the math is terribly complex, but that doesn't make it immutable. Does a unique solution to the Einstein field equations produce a unique time-dilation "field" (in 4 dimensions)? Anyway, I'm stuck using the tools in my toolbox, and I'm currently I'm looking at how time dilation might affect Mercury's precession.
  3. The actual timing mechanism (photon vs spring vs something else) of a clock doesn't matter. If it did we would violate the equivalence principle. Regardless, a photon-clock is a real thing: https://www.caltech.edu/about/news/caltech-scientists-create-tiny-photon-clock-1029 The talk about absorption and re-emission doesn't and can't have any bearing on the rate of the clock ticking for a simple, logical reason that I mentioned earlier.
  4. They have noticed. I think the analogy goes back into the 18th century. The only thing I've done is suggest that it isn't an analogy at all, but two ways of looking at the same thing. I find it odd that you agree that this would be a simplification of GR but also that, if true, you say "it is only because you have based it on GR..." If it reproduces the predictions of GR faithfully, is it redundant and trivial, or does it have value in your eyes? Thanks for the recommendation Joigus. Is this your source for claiming that gravitational time dilation can be attributed to longer absorption and re-emission times? Because I've never heard of that and I'd be interested in a proof because I don't think it's tenable.
  5. Why do you say it doesn't produce the same results? Also, if it was shown to do so, would your reaction be dismissive? Because I'm fine discussing the details but not if you're not sincerely interested.
  6. The "F=ma optics" analogy. The analogy claiming that mass in gravitation behaves like light in a graded time dilation field. Once the analogy is ordained "complete" I don't see the value in solving it for various special cases. I agree that "it works" but I completely disagree that it's irrelevant. It's a matter of personal preference, and how much of a philosopher-at-heart a person is, I suppose. I cannot stand the Copenhagen Interpretation, for example. It's offensive to me, and it baffles me that some folks are at peace with it. If a causal mechanism for gravity is uninteresting or redundant to you, that's OK. I suspect others might find it interesting.
  7. If you're comfortable with the current explanation of gravity in GR, that's fantastic. Many people would not agree, though, and some say we don't have an explanation for it at all. This is Richard Feynman: I'm working on that as a matter of personal satisfaction, but Eddington (and others) claim that the analogy is "complete".
  8. The EM mass is important because it would explain why mass would move in the direction of a graded time dilation field. This paper is predicting no new physics. From a philosophical standpoint, though, it offers: new (likely simpler) ways to analyze old problems, as well as more physically intuitive explanations of the mass-energy equivalence, the cosmic speed limit, and relativistic mass.
  9. OK Strange, thanks for your input. Do you have any feedback on the paper I posted in OP?
  10. In the context of my discussion with MigL and Joigus, I'm using "absolute" to differentiate clocking rates in different gravity wells from what they apparently believe to be "relative' effects. What would be more appropriate? Unqualified? Indisputable?
  11. Hi MigL, I reiterate my last point that I don't think you'll have anything to add to this discussion if you believe this. Observers all agree on the local invariance of c, but the wavelength of photons in a light-clock do not determine its clocking rate. A remote light-clock which is clocking more slowly than mine due to gravity is doing so because the photons in it are literally moving more slowly.
  12. As I said, everyone would agree that a clock in a deeper gravity well clocks more slowly than one higher up. This is not true of two clocks merely in relative motion. The latter is dependent on the frame of the observer, and the former is not. The clocking rate is relative between the clocks, but that differential is absolute for all observers.
  13. No problem, what word would you prefer I use? Time dilation is not illusory, and does not require a local meeting of clocks to reconcile. All observers would agree on the existence of clocking differentials in various gravity wells.
  14. Agreed, but everyone would agree that the clock in a deeper gravity well is clocking more slowly. Bringing the clocks together for comparison is irrelevant (unlike the twin paradox, for example).
  15. That's why I'm here, friend. I'm asking for feedback. I've provided the references for my paper, and those references seem pretty thorough. The concept of "F=ma optics" has been studied for over a century, and the derivation is well established. The concept of EM mass is relatively new (~30 years) but still has many papers published in high-profile journals. It doesn't matter how we compare. Bring the lower one up, bring the higher one down. Both parties use telescopes. Morse code. Carrier pigeons. We wait a year, there's a difference in time passed. Wait 100 years and that difference is 100 times greater. If you don't believe that gravitational time dilation is an absolute phenomenon then, with respect, I don't think you'll have much to add to this conversation. The corrections made to the GPS satellites to account for gravitational time dilation are there for a reason.
  16. Gravitational time dilation is absolute. Take two identical watches which (let's say) use photons for timing, and place one more deeply in a gravitational well. It is not an illusion that the one in the gravitational well clocks more slowly. It has nothing to do with the wavelength of the the timing photons. Pound-Rebka only applies to radial movement.
  17. The red-shifting/blue-shifting only occurs with movement which is radial to the gravity source. The difference in the apparent velocity of photon movement in various gravity wells, which is perpendicular to the gravity source, cannot be due to "slower or faster re-emission" from atoms because it is independent of distance traveled. In other words, a photon travelling 1 light-second "up here" may take 2 light-seconds "down there", but then a photon travelling 10 light-seconds "up here" would take 20 light-seconds "down there". I don't think anyone believes that the emitting atom down there is actually holding on to that photon just long enough to give the illusion that the photon's future speed has been reduced. The causal mechanism is the time dilation field refracting the EM mass. I believe it does generalize. What we call space-time curvature in GR can simply be reframed as a time dilation field, and the effects of gravity are already accounted for.
  18. I don't personally know this but that was my impression. If we don't believe that it's true then my confusion is actually resolved...kind of. My layman impression of energy in GR is that its form is irrelevant (mass or otherwise), and that energy density contributes to the local gravitational field. The crux of my confusion is that momentum energy is frame-dependent, whereas black hole creation is obviously an absolute event. If we allow angular momentum energy to contribute to the creation of a black hole, but really scrutinize the difference between angular momentum energy and linear momentum energy, then I'm left with questions.
  19. I'll try my best, but I do not appreciate the difference between being "covariant under general coordinate transformations" and being "covariant under inertial frames". Isn't the latter just special case of the former, and doesn't the latter fit the scenario we're discussing? In any event, I'd like to keep acceleration out of this, for simplicity. MigL read my intention correctly in that the original mass was "given" momentum energy by simply changing frames. Sorry for the confusion.
  20. I'll check that out, thank-you! Photons do not slow down locally, I agree, but remote photons must slow down. If you're wearing a watch which uses photons as a timing mechanism, and I'm wearing the same watch but sitting far above you in a powerful gravity well, how else could I explain that your watch is ticking more slowly? You can claim that it's merely an illusion because it isn't local but that point 1) is debatable (because it's an absolute effect) and 2) irrelevant to the analogy, because prism refraction is locally absolute. Regarding EM mass, I suggest that you read the cited references, particularly http://home.claranet.nl/users/benschop/homepg2/electron.pdf. The authors have published many peer-reviewed articles on the subject. I find it fascinating, personally. Cheers,
  21. I think I distracted the thread when I said "and we accelerate it [the object]." We could alternatively observe the mass, which is just on the brink of black hole collapse, after we have gone under acceleration ourselves such that the mass now apparently has sufficient energy to collapse. The answer has already apparently been given, which is that the stress-energy-momentum tensor is covariant in inertial frames. To me, this generates more questions. We know that a rotating mass requires less rest mass than a non-rotating one for gravitational collapse. This could be explained by observing that angular momentum is absolute, and that the mass is under acceleration due to rotation, therefore all inertial frames will acknowledge it... But what is a rotating mass, exactly? What about a binary star system rotating at speeds sufficient to predict black hole creation? The stars, A and B, would each claim to be free-falling and not under acceleration. They would each calculate the other body to be orbiting them at extraordinary speeds. A remote observer C could predict that the A-B system should collapse to form a black hole, but does that analysis work for either orbiting body?
  22. Abstract In this speculative paper, we show that electromagnetic (EM) mass and general relativistic time dilation are sufficient to predict gravitational attraction. Time Dilation as Refraction First, we consider light moving slowly through a local medium with a large refractive index; we then observe a remote light ray moving slowly in a large gravitational field due to relativistic time dilation, such that their respective apparent velocities are equal, and recognize the opportunity for a potential equivalence. Exploring this, we create a spherical refractive medium whose index varies with the distance from its center by the following: where r is the distance from the center of the object and rs is the Schwarzschild radius of some gravitational object O with mass m which we are attempting to emulate. What we discover is that light passing through such an object at a given radius r will behave identically as it would while passing by O at the same radius. This phenomenon, known as the optical-mechanical analogy (or more recently as F=ma optics), has been well-established and extensively studied over the last century. [ref 1-3] As Sir Arthur Eddington wrote [ref 4] in his famous 1920 summary of General Relativity, “Space, Time and Gravitation”: The efficacy of the “F=ma optics” is without doubt, however, respective authors on the subject are careful to stress the purely analogous nature of the relationship. We would like to suggest that it isn’t an analogy at all, but rather a literal equivalence. EM Mass Let us envision an electromagnetic wave, with a wavelength of 2.43 * 10-12 m, moving in a periodic cycle which takes it back upon itself such that it becomes a self-reinforcing soliton. The complete orbital path length of this EM wave is equal to its wavelength but is such that it makes a double-loop. (see Fig 1) Such a quasi-symmetrical object, if stable, would resemble an electron. It would have a physical radius of on the order of 2.43 * 10-12 m / 4𝛑, an electric field, a magnetic dipole, and a half-integral spin [ref 5, 6]. It would also offer a physical manifestation of Einstein’s mass/energy equivalence (e.g. “releasing” the photon from its self-contained path would result in a burst equal to its “rest energy”). Cosmic Speed Limit Philosophically, many of us have been mystified by the limiting nature of c. EM mass might provide a straight-forward explanation -- a photon turning back upon itself does not follow the traditional geodesic between two points. As an EM mass particle is accelerated, a larger portion of its photon’s circuit is thus spent moving in the direction of its velocity; this percentage can be arbitrarily close to, but not quite, 1. (see Fig 2) Transverse Waves If we refer back to our sphere of graded refractive index, we would expect that the path of light moving radially to it would remain unaffected; only a light’s path with a transverse component would be altered. The photon of an EM mass particle moving in a closed circuit within the sphere would possess a transverse portion of its path relative to the center of the medium in a range between .5 and 1, depending upon the relative velocities of the sphere and the particle. This could manifest as relativistic mass. Conclusion In this paper we have shown the connection of optics to the gravitational bending of light in a graded time dilation field. Additionally we have shown that if mass were to possess an electromagnetic nature moving in a cyclic fashion (i.e. “EM mass”) then we are able to precisely predict the gravitational behavior of that mass in the presence of such a time dilation field without invoking any other mechanism related to General Relativity. Lastly, we are able to show that this model may plausibly explain other aspects of Relativity, such as the limiting speed of light and relativistic mass. We feel that these aggregate theories provide ample potential to warrant further investigation. References [1]The optical-mechanical analogy for stationary metrics in general relativity; Paul M. Alsing; American Journal of Physics 66, 779 (1998); https://doi.org/10.1119/1.18957 [2] The optical-mechanical analogy in general relativity: Exact Newtonian forms for the equations of motion of particles and photons; James Evans, Kamal K. Nandi & Anwarul Islam; General Relativity and Gravitation volume 28, pages 413–439(1996) [3] ‘‘F=ma’’ optics; James Evans and Mark Rosenquist; American Journal of Physics 54, 876 (1986); https://doi.org/10.1119/1.14861 [4] Space, Time and Gravitation; Sir Arthur Eddington; http://www.gutenberg.org/files/29782/29782-pdf.pdf [5] Sumana Bhadra, Electromagnetic Mass Models in General Theory of Relativity: https://arxiv.org/abs/0710.5619 [6] Is the electron a photon with toroidal topology? J.G. Williamson and M.B. van der Mark, 1997; Annales de la Fondation Louis de Broglie, Volume 22, no.2, 133. http://home.claranet.nl/users/benschop/homepg2/electron.pdf
  23. Hi there! "Black hole creation" is obviously an absolute event at a given point in space-time, and black holes are created when a particular energy density threshold is reached. My problem is that kinetic energy is a relative calculation. If a mass is sufficiently dense to be close to the Schwarzschild radius, and we accelerate it, we can obviously surpass the required density threshold according to our frame. How does general relativity reconcile this?
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