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The victorious truther

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Posts posted by The victorious truther


  1. On 10/18/2020 at 7:23 AM, John2020 said:

    Because I addressed the rotational energies coming from the torque (nut) and counter torque (upon the screw), where both have opposing direction of rotation (conservation of angular momentum), thus they cancel each other.

    At some point the whole thing is at rest then at a later time it's moving at a constant linear and angular velocity with respect to its center of mass. Thusly, there wasn't actually any conservation of angular momentum or energy because work was done (in this case both linear as well as rotational work). Energy was not in fact conserved if this bolt went from not moving to moving. 

     

    26 minutes ago, John2020 said:

    I am preparing a drawing to explain all these and we will make the analysis for three cases: rigid rope, semi-rigid and non-rigid rope.

    If you are truly to do this correctly you CANNOT be ignorant to what frame of reference you are in whether inertial or in the rotating frame of reference. Further, fully analyze it from the inertial frame of reference then move into the non-inertial one with mathematics to back up your conclusions. 


  2. On 10/18/2020 at 10:48 AM, John2020 said:

    Then it has to be utilized in a rotating frame. Creation of an Euler force.

    If it doesn't work when seen from an inertial frame of reference then it doesn't work at all.

    On 10/18/2020 at 10:56 AM, John2020 said:

    In an accelerating spinning chair will appear centrfugal and Euler forces. They should be possible to be  utilized.

    The only force that can be utilized is the one that is actually accelerating you. Fictitious force only arise and are present in non-inertial frames of reference because mathematically we attempt to treat an accelerating frame of reference as if it actually is at rest so we have to make up other forces to give rise to the phenomenon we observe while remaining at rest in that non-inertial frame of reference. Those forces which do not disappear after we switch frames of reference from say non-inertial to inertial (centripetal force for example) are the only real forces that you can do anything with. 


  3. On 9/25/2020 at 8:20 AM, michel123456 said:

    Because he uses the laws of Relativity exactly in the same way. So B observes A aging less, and A observes B aging less. They are observing THE SAME THING.

    If you make a spacetime diagram of this situation in which one twin remained inertial while the other had a device to measure that they flipped frames of reference (remember it's relativity of inertial frames of reference not relativity of NON-INERTIAL frames of reference) then with a instantaneous turn around the non-inertial twin would notice the other twin actually jump ahead in time in a way the other twin (inertial one) would not see. If you plot the diagram you'll notice the time loss as a missing triangular section if I recall.  

    On 9/25/2020 at 10:27 AM, michel123456 said:

    But A is also at rest. He sees (observes, measures) the Earth length contracted & the distance to the Earth is also contracted. A & B must be considered on the same ground. The situation is symmetric, reversible, how to say. Motion is relative: there is no Earth at rest & A travelling.

    No, both WORLD LINES cannot be treated entirely as the same as the moving twin CHANGES frames of reference half way through his journey (his proper time). So it isn't symmetric just as if a car drives away and comes back we know it was the car that accelerated (changed inertial frames of reference) as it was not the person given they both had accelerometers. If they both remained inertial then they would never meet back up again and if they were both non-inertial then their accelerometers would have noticed the inclusion of some force fictitiously into each of their respective frames of reference but the person on the ground never noticed such inertial forces arise so the only conclusion is that the car was moving, ergo it WASN'T symmetric. Why is this so hard to understand when you literally can go into a parking lot and forget about special relativity to then show this to be the case. Remember that special relativity has to simplify down to classical physics in the low speed limit. 

    Also, acceleration is not relative in the sense that velocity is or inertial frames of reference are just as in CLASSICAL PHYSICS or in GALILEAN SPACETIME. In special relativity (as in classical physics) it isn't relative whether you are ACCELERATING or are ROTATING. We can disagree the magnitude of said quantities but whether you are or are not accelerating is not frame dependent but can rather frame independent. 

    @michel123456 Do you understand that the postulates of special relativity are:

    1. All inertial frames of reference are to be treated as equivalent in that the laws of physics behave the same in any inertial frame of reference.

    2. The speed of light as measured from any arbitrary inertial frame of reference in free space is constant. 

    This would mean that if you had a ANY non-inertial motion then by definition we could detect it and know that we are in a non-inertial reference frame because these postulates wouldn't apply. Further, this would also mean the situation of one non-inertial observer compared to an inertial one (the twin paradox) would mean by these postulates that their world lines COULD NOT be treated symmetrically or in other terms equivalently as if the non-inertial reference was inertial. AGAIN, the postulates are not, 

    \( 1^{*} \). All frames of reference have the laws of physics behave the same within them. 

     \( 2^{*} \). The speed of light as measured from any frame of reference in free space is constant. 

    You seem to be under the delusion that the starred ones are what define special relativity when in relativity it's the un-starred ones. 


  4. 6 hours ago, joigus said:

    And @The victorious truther, you misquoted me.

    I must supremely apologize then. I must have missed some important context involved when I abruptly popped in here. 

    6 hours ago, Eise said:

    As space and time are relative, but spacetime is not, this is no problem at all.

    Stated differently there is no relativity principle for non-inertial frames of reference in classical or relativistic physics. 


  5. 9 hours ago, joigus said:

    I offer this thought, in all humility - if Special Relativity theory can generate the above 6 long, complicated pages of debate among highly intelligent people,  without their being able to reach any agreement about what it actually means, as appears to be the case -  could this be because the theory isn't right?

    A theory such as special relativity or general relativity can be a successful well understood mathematical/theoretical and applied theory of how the world works. Yet we could still disagree on philosophical interpretations of the relationship of our naive realism and previous theories with their accompanying previous ontologies to this specific theory (as well as fully interpreting the theory itself). Take the discussion of proper mass and relativistic mass and ask the legitimate question of whether one/both/neither of these newer concepts in special relativity would match up intuitively/ontologically (philosophically) to the classical physics concept of inertia (mass). Is relativistic mass the relativistic counterpart to inertia or is this a false comparison? This is a legitimate question but it doesn't really come to much difficulty when it comes to actually applying said theory if you had a case to make that we applied it, expected a certain result but got the wrong one, but under a different interpretation the experimental results could be construed to be correct then i'd agree there is something contentious. . . i'll await for you to actually propose this. 

    In the history and philosophy of physics the discussion of what forces are as well as whether we should even accept action-at-a-distance ones wasn't settled with Newtons Principia but this philosophical side discussion didn't stop us from applying successfully the mathematical results there in for generations. 

    7 hours ago, michel123456 said:

    1.I hope I have that much

    You just said your biased. . . 

    7 hours ago, michel123456 said:

    2. Again, Relativity is OK to me as long it is considered as a Theory that describes (between others) a phenomena comparable to perspective: a kind of effect caused by the different states of motion of different observers, a Theory that explains how one observer can relate his observation to another observer.

    Which is technically what the GALILEAN transformation already did in CLASSICAL physics but I do not see you screaming at the top of lungs about that and how it must be a perspective thing. Classical physics did the same thing of relating certain quantities in one frame of reference to that of another but they were no less real with respect to those frames of reference. 

    7 hours ago, michel123456 said:

    Taking the example of length contraction, it seems evident (to all of us I hope) that once the traveler stops, the resting observer does not observe length contraction anymore,  the phenomena has vanished.

    Be careful with your language here. . . novice. . . when you say STOP it's implied you mean non-inertially accelerate or change reference frames so that they entered the specific one in question. Obviously if we go to classical physics in which a person who was moving with respect to our frame of reference then suddenly de-accelerate to enter our frame of reference. . . they aren't moving any more. . . cause they stopped with respect to our frame of reference. . . so if you ask whether the non-moving observer is moving then clearly no. . . because they aren't moving. To be length contracted or appear as such from other frames of reference the object in question would have to be moving. 

    7 hours ago, michel123456 said:

    In fact, in his own FOR, the traveler was never contracted at all: length contraction is an observational effect that appears from the FOR of reference (at rest). Exactly as the forearm presented in perspective: it does not change length. Is this doubting of Relativity?

    Velocity is a real effect. . . but it's frame dependent on whether it arises and you won't see the same thing from every frame of reference nor could you claim that one particular velocity was more real or not or even declare that he is actually at rest when in other frames of reference he is moving. If this was purely a perceptual effect then we would think this wouldn't be accompanied by clear dynamical and kinematical issues involved with taking measurements. . . course you could mathematically reproduce this understanding with a classical theory of literal length contraction (as well as a counterpart one with no length contraction but finite speed of perceptual effects) and compare. . . to you know. . . show who is right. 

     


  6. 7 hours ago, michel123456 said:

    Quest1. Why is the distance d2 larger than the distance d1? Shouldn't it be contracted?

    How about you go through the mathematics and create an image plane with the relativistic object having its light happen to reach some focus then figure it out. It's difficult and perhaps not actually correct to analyze some image analysis as has been given as we do not know what the units were nor whether your naive perceptual decision on what is longer is truly correct. Should the image of a cube appear larger than it should in the way you claim or is this not what special relativity would predict optically? Remember, no "I think it would look like this," just do the mathematics or perhaps wait for some one competent in that respective to show it in a simplified situation.  

    7 hours ago, michel123456 said:

    Quest2. Why is the red distance smaller than the orange one? I am counting 4 intervals for the red one (4 squares) and 8 or more for the orange one. If the cube is moving at constant velocity, the 2 lines should be equal.

    A simple imaging plane and a focus will construe the image like that as objects farther to the left will appear more scrunched together i'm assuming. . . we're talking about what you would see optically. In fact. . . just you wait as i'll perform the some mathematical investigation into this but derived via some simple vector mechanics with objects being focused unto an imaging plane with a focus. Then we can compare the images showing that those objects farther away parallel wise to the imaging plane do seem to have their distance scrunched up even if we happen to possess an equally dispersed series of lines in reality

    7 hours ago, michel123456 said:

    And I have to admit that I had in mind picture B. I was wrong again as it seems. But I still don't know why: in this picture B everything looks fine.

    Glad you admit your fault and you must please understand that you should not use your intuition as if it's a judicial gavel of physics as even in CLASSICAL PHYSICS with optical imaging i'm willing to bet we could both make similar mistakes in thinking if we didn't actually do the proper mathematical preliminaries to derive how things would actually play out. I'll attempt to get back to you as soon as possible for the classical then the special relativistic case with all proper mathematical foundations. I'll be using equally spaced constant velocity rods then for both the classical as well as the relativistic to compare. 

     


  7. 1 hour ago, michel123456 said:

    Nicely presented. Except that intuition would say that the guy who covered the long path through the corners would be older than the one going straight away, while the result of the twin paradox is the contrary.

    You would think this if you didn't consult the spacetime interval in which \( s^{2} = (ct)^{2} - x^{2} = (c\tau)^{2}\). NOTE that the traveler happens to have a longer path through spacetime and together with the objectively long path they traveled in space some of that distance in SPACETIME that they happened to traverse has some of that temporal component eaten up by the distance they traveled. 

    The spacetime interval for the person at rest is: 

    \[ \tau = t_{person at rest} \]

    For the twin who (because he was non-inertial) was objectively traveling a longer path through spacetime they started and ended the journey at the same spot yielding in terms of the rest frame time \( \tau \) or it took \( \tau \) time for them to leave then come back: 

    \[  (c\tau)^{2} = (ct_{traveler})^{2} + x^{2} \]

    They traveled objectively some certain distance \( x \) and using your knowledge of pythagorean theorem you notice that the length of the one side (the time by the traveler) couldn't exceed the length of the two others. Objectively given they traveled away there was no way the time of the traveler could in fact exceed or even equal that of the time given by the clock at rest if it must abide by special relativity and likewise the spacetime interval. 

    \[ t_{traveler} \neq \tau \]

    @joigus Did I do this right? 

    14 minutes ago, md65536 said:

    Michel has established that he's spent 20 years denying relativity. There are many, many hijacked threads over the decades, any that have certain keywords (in this case, "time, direction"), turned into 6+ pages of failed attempts to get him personally to accept something about SR. He's stated in this thread that he's not interested in relativity, and of all the hundreds and hundreds of answers to his repeated questions, not a single one of them he acknowledges as an answer to his questions. The only time I've seen any calculation or attempt to work through a problem, is when he's twisting his beliefs and made-up definitions into a nonsensical answer that confirms that relativity is wrong. Trying to understand relativity is destructive to his goals, and completely avoided. So the answer is yes, anything that shows relativity working will be ignored. If you're enjoying explaining it, that's good. If you're hoping Michel will learn something, ... I wouldn't.

    Always bound to come across somebody like this on any forum. . .


  8.  

    12 hours ago, michel123456 said:

    The analogy with length contraction is pure coincidence, I guess.

    Or not. Are the laws of physics a single thing that enties everything ( the way we see things on a daily basis), or are the laws of perspective totally independent of Relativity? (as it seems to be the case at first sight).

    And respectively, can Relativity ignore the fact that objects appear smaller as their distance from the observer increase? And not taking count of this effect when representing the distortion of objects that move at near to c velocity?

    The arm does look smaller or larger depending on your perspective. . . but if you actually made a measurement and sent a light beam (or a radio signal or even used a measuring rod that was at rest with respect to your arm) you would happen to find the length had remained unchanged in BOTH situations. So. . . no length contraction. . . bad analogy. 

    When you talk about the laws of perspective being independent of Relativity note the difference between what a camera or perhaps even a human being could potentially see and what kind of raw measurements we could make in which these sort of perceptual effects wouldn't come into it. You get the SAME PERCEPTUAL effects in CLASSICAL PHYSICS and we rightly so do not designate them as actual length changes but this is because of the specific collection of dynamical/kinematical laws we are assuming to then analyze this. The same is in special relativity in which length contraction is usually treated as the sort of frame dependent observation that is consistent with Lorentzian transformations while what you would see is (c) instead of (b) so you CANNOT go off of pure visual observations so to speak to find this contraction but you would measurably notice it in special relativity,

    PWAug19Appell-fig2a_1200-635x1518.thumb.jpg.7a0e73252c9146de461f811686fc10f6.jpg 

    Not only that. . . are you just going to ignore the meat of my previous posts. . . anything to say. . . the laws of optics are not ignored in special relativity rather they are amended yielding the above image (c) rather than the classical optical image (e). If you desire to chalk it up to CLASSICAL OPTICS then please be my guest and explain how this can be the case that in special relativity we seem to measure/record lengths as being shorter when in reality they are not supposed to be but we measure them as. 

    Further, there isn't entirely something wrong with the philosophical question of whether it's the dynamical laws that give rise to or are fundamental to the kinematical ones or vice versa as other philosophers in spacetime philosophy have claimed that dynamical symmetries must be symmetries of spacetime. Dissenters have argued that we should flip the arrow of explanation from the kinematically explaining dynamical laws (spacetime structure -> dynamical laws) to seeing them as rather fundamental (dynamical laws -> spacetime structure). The question then of whether the Lorentz length contraction is more real in one perspective or the other one isn't really a question that would get a wrong answer in this situation as if we emphasized dynamical considerations then the objects from other perspectives do contract seemingly (dynamical laws require us to measure them as shortened) or it's the spacetime structure that results in our. . . wait for it. . . length measurements to result in being shorter. In either situation it wouldn't be any less real or entirely more perceptual


  9. 7 minutes ago, md65536 said:

    Thanks for the interesting visuals, they're rarely shown.

    So true numerous different misconceptions in relativity or perhaps other areas of physics could be alleviated with sort of thinking. 

    8 minutes ago, md65536 said:

    From what I understand, the only(?) difference between the length-contracted measured (b) and the seen (c) is the effect of abberation of light, where the orientation of a ray of light is different in different frames of reference, due to the time that it takes light to travel from source to destination while those points are moving.

    The time it has to travel as well as where and when it was emitted as even in your frame of reference in special relativity it's perfectly possible to imagine being in the cube's frame to emit light equally in all directions at the same time but others will not see it in the same manner you would expect. 

    10 minutes ago, md65536 said:

    The rotation seen must be a rotation in 4 dimensions, nothing is rotated in 3? To demonstrate, if you add rails that the dice slide on (say 4 rails that 4 edges of each die slide on), such that the rails are at rest relative to the observer, you'll see of course that the rails do not appear distorted, and that the dice edges never appear to leave the rails. For example, the tops of the 1-side of the dice still appear to follow an undistorted straight line, and the bottoms of the 1s follow another, and same with the 6-side at the back. When moving in the x direction, an objects's parts don't rotate off their yx coordinates, but instead appear stretched between them. That can also be seen in the black and white animation you posted earlier.

    You know I think you may be rather right in your speculation but i'd have to investigate further mathematically. 

    @md65536 Also. . . Steins Gate. . . NICE! 


  10. 6 hours ago, michel123456 said:

    That is worth a separate thread. Some Moderator will send me a warning & do the job (I hope) with a link here for those interested.

    A comment from Swansont about the same topic some posts above says:

    Please do so but i'm not sure I trust you with deriving the visual results from special relativity on what you would see so when you get there stick to classical physics. . . unless you can show us the mathematical rigor needed. 

    6 hours ago, michel123456 said:

    The laws of perspective (that try to represent our visual  everyday experience) say that an object that gets away from you is seen as if its size was diminishing, and an object that gets close to you is seen as getting larger.

    Yes, there is also a classical assumption that would play into this and give rather predictive results as to how it would exactly look. Cut your teeth on this article I found. 

    6 hours ago, michel123456 said:

    Of course the object does not change size in "reality", it is simply an effect of optics, but as I read here, it is completely ignored in Relativity. The moving examples posted above by V.T. do not care about this perspective effect.

    Hmmmm. . . I found it! There is a difference between length contraction (measured) and what is observed which respectively would be (b) versus (c) as well as what you would expect with naive classical physics (e). 

    PWAug19Appell-fig2a_1200-635x1518.thumb.jpg.3bcf8b17e2fa148b5944b78341af7626.jpg

    (a) A row of dice at rest moving from left to right in a single file at 95% of the speed of light. (b) The moving dice are length contracted, so that one might (wrongly) expect them to look as here. (c) If you actually observe the dice, however, they will appear rotated. (d) But when some perception in depth is provided, you’d see them as sheared rather than rotated. (e) Shown here is the predicted “classical” appearance of the dice, with no length contraction. You can view a short film of part c online here. (Courtesy: U Kraus 2008 Eur. J. Phys. 29 1)

    6 hours ago, michel123456 said:

    Or not. Are the laws of physics a single thing that enties everything ( the way we see things on a daily basis), or are the laws of perspective totally independent of Relativity? (as it seems to be the case at first sight).

    And respectively, can Relativity ignore the fact that objects appear smaller as their distance from the observer increase? And not taking count of this effect when representing the distortion of objects that move at near to c velocity?

    You better have read the articles above and looked at the image as well as considered that there is a strong difference between what length you measure an object to have and distorted image you see.  


  11. On 9/17/2020 at 3:25 PM, michel123456 said:

    Third problem is length contraction happening only in the direction of movement. I wonder how that can happen, while time dilation has no direction. How are the 2 effects compatible? (it would make more sense if length contraction happened in all directions. More sense if length contraction was a kind of illusion, a kind of perspective effect and not a real thing.

    It does only happen in the direction of motion as is or would be derived from the Lorentz transformation. If you have some other mathematical model to propose in which the object doesn't just contract in the direction of motion but in every direction equally or by some function of the velocity be my guest. . . propose it and test it. Further, "time dilation has no direction" why does this have to be a problem. . . why is this a problem for length contraction? Again you can propose some inhomogeneity or anisotropic effects that if a clock went in one direction it would slow more than in another in a round trip. . . be my guest in mathematically realizing this and testing it.  

    On 9/17/2020 at 3:25 PM, michel123456 said:

    Fourth problem is with multiple realities; how is it possible for all observers to measure different realities (different times & lengths) and that these realities are all existing at the same time: aka you have a rod 1 meter long in your hand but some other observer in a moving car tells you that you are wrong, the rod is 90 centimeters. If someone told you that you would probably answer that you know better, the rod is 1meter long, point. What the other observer is measuring is a distorted image, it is not a 2nd reality.

    You cannot just assume there is this immaterial Newtonian Clock that ticks throughout the universe and some how also minimally interacts with everything in the process assigning a precise time measurement anywhere in the universe. . . you cannot just claim this by fiat.

    Further, you literally DO NOT HAVE TO LEAVE GALILEAN RELATIVITY or classical physics to have your "multiple realities". Remember the Galilean transformation? Through this transformation you can transform from one INERTIAL frame to another without issue and thusly could show that the laws of physics (conservation of energy/linear and angular momentum) were followed in both frames of reference just as YOU will see the other frame moving away from you with some velocity (they are not identical frames of reference then) according to your frame of reference. . . wait. . . but the velocity was opposite that way in the other inertial frame of reference. . . which is the right velocity? In which the answer to said question is that this is a nonsense question as only a velocity assigned to a particular frame of reference (even the almighty stationary one) is what matters as you can only ask what velocity an object has with RESPECT to a particular frame of reference. In special relativity this idea is merely extended to measurements of lengths as well as clock ticks seen from your frame of reference. 

    On 9/17/2020 at 3:25 PM, michel123456 said:

    Ah yes, fifth problem: the twin paradox. The paradox is not about one twin aging more or less than the other. The paradox is that there is a broken symmetry: the traveling twin is aging less than the twin who stays at rest. But since the traveling twin is also in a resting FOR (a different one), who is the traveling twin? twin A or twin B? Which of the 2 twins will age less than the other? It is not logically acceptable that both twins will age less than the other. That is the paradox. And there is something wrong in it.(and not endless conversations about accelerations in order to determine who is the traveler & who is at rest, that is not the problem)

    And maybe more. 

    Again, you do not need to leave classical physics to see the fault in seeing this as a problem. Imagine you have a spaceship and a lone spaceman out in the middle of space at rest with respect to each other. The spaceship rockets away accelerating up then slows down to speed up in the opposite direction before slowing down again to enter the original frame of reference it resided in at the beginning. You both ask each other who really moved?

    First Person: I clearly didn't as I saw you speed away and during the whole time I remained at rest with respect to myself. I wasn't moving.

    Second Person: But I also saw myself as at rest the whole time. 

    When you think about it kinematically and visually they both have some grounds to consider themselves both correct as there space-time diagrams would show similar but oppositely oriented collections of parabolic curves. To alleviate the issue we decide to mount an apprautus to the spaceship that is basically a small ball within a larger ball where the smaller ball is floating freely but the larger ball is attached to the spaceship. If we accelerated forward then the freely floating ball would just slowly float in the air until the now moving outer surface closed the distance and then impacted it. If we were in an inertial frame of reference the whole time then clearly the ball within there would just float as you would expect via our classical understanding of physics and inertial frames of reference (frames without any induced forces). You then both repeat the same experiment and predictably the floating spaceman would never notice any forces (fictitious or real) creep into his frame of reference while those in the spaceship would see their smaller ball begin to move as if some force was exerted on it but (assuming they accounted for all other forces) this cannot be as it clearly must remain inertial as we accounted for all forces. The only real answer is that a force was exerted on the spaceship which gave rise to our fictitious force on the ball. Thus the paradox is solved. . . the spaceship was the one that moved. 

    With two inertial frames of reference (one moving away at constant velocity) you couldn't really do this because the paradox requires the frames come back together and if they both accelerated away then came back together they would still see the fictitious forces arise in their respective frames of reference. 

    Just as in Galilean or classical physics there is NO RELATIVITY OF NON-INERTIAL FRAMES OF REFERENCE so is the case in special relativity because. . . you know. . . its first postulate is that all inertial frames of reference are equivalent not ALL NON-INERTIAL FRAMES OF REFERENCE ARE EQUIVALENT or ALL FRAMES OF REFERENCE ARE EQUIVALENT. Which would be required for the twin paradox in that one of them has to turn around so to speak or both equally turn around but in the process in both situations their are people objectively changing inertial frames of reference. In the later case, however, given they accelerated for the same amount of proper time (slowed then speed up to come back) they would have identical world lines and there wouldn't be any net time difference with respect to each other when they re-enter the original inertial frame of reference because they would be entirely symmetric. . . the people in the original frame of reference however would notice that they were both equally younger assuming they remained inertial (we could as an experiment or mathematically set up a similar ball apparatus as before). 

    On 9/18/2020 at 2:44 AM, michel123456 said:

    Not to say that the laws of optics should be derived from Relativity, since it is a theory that deals with what is being observed.

    This is an issue I see all the time in people trying to grasp relativity. In the theory (with minimal ontological assumptions of Minkowski spacetime) while you have this effect of length contraction that is rather mathematically explicit even by theory or ontology what you would actually observe is something like. . . Animated_Terrell_Rotation_-_Cube.gif.826392720aa377b16ead0471b11a2ead.gif

    In fact I'm pretty sure there is even a further different classical perspective of the cube that you would expect which does differ from the visual image seen above that special relativity would, being approximately correct, in the end expect. 

     

    @swansont How'd I do? 


  12. 10 hours ago, geordief said:

    Are you saying that if we had an absolute preferred  frame of reference that the laws of physics would vary from place to place?

    Depends on what relationship "c" has to do with physics and the ontological entities we familiarize ourselves with as well as the dynamics of spacetime itself. We could go the direction of some philosophers and postulate that the structure of spacetime is different to the dynamical symmetries of physical systems (in this case the Lorentz invariance of the laws of physics and the admittance of a fastest casual speed). All that is required here is Lorentz invariance as far as i'm aware and whether spacetime has a hand in it or not is a different interpretational discussion to the clearly experimental fact of Lorentzian invariance. 


  13. 9 hours ago, Duda Jarek said:

    Looks like GEM approximation of general relativity (confirmed e.g. by Gravity Probe B): https://en.wikipedia.org/wiki/Gravitoelectromagnetism

    You can use standard methodology/tools from electromagnetism for that, like avoiding PDEs with Green's function e.g. in static https://en.wikipedia.org/wiki/Biot–Savart_law or general https://en.wikipedia.org/wiki/Jefimenko's_equations

    ps. Kepler problem simulator using this approximation: https://demonstrations.wolfram.com/KeplerProblemWithClassicalSpinOrbitInteraction/

    Damn you are perceptive, yes i've heard of the GEM approximations and have thought about different approaches to defining the gravitational field. Given gauss law for gravitation, with the analogy to therefore electromagnetic waves, it makes sense that as an approximation or for personal investigation that I would merely use an inhomogeneous wave equation. Guess i'll just jump into it with the Jefimenko's Equations you linked to assuming they are synonymous with a gravito-electromagnetic field. The problem would be then discretizing it and then integrating. If you know how to do that with these equations or have resources that would be appreciated but i'll see what I can do on my own first then get back to you. 

    6 minutes ago, joigus said:

    Duda is right AFAIK. You cannot picture solutions to inhomogeneous eq. by propagating the profile of the static source, which seems what you're naively doing in your link. Inhomogeneous eq. behaves differently. You need the Green function. Then you have retarded solutions in terms of the density. Or you could just plot Lienard-Wiechert-like potentials by relating constants and eliminating indices.

    Eliminating indices? If you are talking about tensors you are going to lose me rather quickly. I've sort'a looked into tenors but not much. 


  14. 7 hours ago, Markus Hanke said:

    Well, GR is a purely classical theory, so it "knows" nothing about quantum fields. So far as GR is concerned, given a small region of spacetime, there is either energy-momentum, or there is a vacuum - which then means a completely empty region. The important thing to remember is that the absence of energy-momentum in some region does not necessarily imply a flat spacetime.

    As far as that interpretation goes but this depends on whether you identify spacetime as distinct from matter and its configurations (classical substantivalism), that it cannot exist in the absence of matter with its accompanying configurations (relationism), or that matter is fully identified with a specific spacetime region so an empty spacetime is basically a spacetime devoid of quantum field looking spacetime configurations (super-substantivalism).

    You can even speculate whether it would mean anything for there to be spacetime without matter in GR without resorting to having to construct a new theory but newly analyze it again. In that arxiv article, while I cannot fully vouch for its veracity, presents the intriguing possibility that even in a universe thinly distributed with matter you could still get back a spacetime that was geometrically Minkowskian. We are assuming that spacetime could take on background inherent geometries independent of the mass distribution (as there isn't any supposed matter) in the empty spacetime. 


  15. Dear scienceforums.net, 

    So i've tried indulging in doing simple python simulations of gravitational phenomenon and have been thinking about simulating a form of gravitation given by an inhomogeneous wave equation version of gauss law of gravity. This is for a personal interest of mine and not because I think such a representation of gravitation would actually be more successful in matching observations. Though i'm fairly curious as to what you would expect in terms of galactic rotation curves with such a simple time retarded potential theory of gravitation. The equation is given below, 

    \[  \nabla^{2} \phi - \frac{1}{ c^{2} } \frac{\partial^{2}  \phi }{ \partial t^{2} } = 4 \pi G \rho. \]

    Basically its a wave equation with a source and thusly I would expect that if I were to simulate this with a finite difference approximation, given no restrictions on the borders, \( f(x) \) initially is that of a single point of density at the origin, you would get something like this (click play on t). However this isn't what I get from simulating a single point at the origin with some finite value for all t, 

    \[ \frac{\partial^{2}  \phi }{ \partial x^{2} } - \frac{1}{ c^{2} } \frac{\partial^{2}  \phi }{ \partial t^{2} } = f(x,t) . \]

    Instead it just blows up so I must be thinking about this wrong. 

    The equation for the discretization of the 1 dimensional wave equation with a discretized source is, assuming \( \frac{c \Delta t}{\Delta x} = 1 \), 

    \[ \phi^{t+1}_{i} = \phi^{t}_{i+1} + \phi^{t}_{i-1} - \phi^{t-1}_{i} - g^{t}_{i} \]

    Sincerely, freshman going on sophomore year


  16. 1 minute ago, Strange said:

    You can model empty spacetime. Obviously there is no such thing in our universe.

    Assuming we got the interpretation right. 

    2 minutes ago, Strange said:

    So you are saying that the muon knows when to decay by looking at the lab clock?

    No, i'm saying that relationally change occurs around it so that even if you were to regard the decay as purely random and before said decay it retained it's properties monadically in the most perfect sense it isn't in the absence of change (relational/monadic). Never said time or change is casually resulting its decay only that it isn't in the absence of change (system wise - greater universe) nor soon to probabilistically under go one. 

    4 minutes ago, Strange said:

    GR only works if space and time are continuous. But then again, we know that GR probably needs to be modified at quantum scales.

    Good article on the possibilities here: https://www.forbes.com/sites/startswithabang/2018/06/14/are-space-and-time-quantized-maybe-not-says-science/

    Why thank you. 


  17. 26 minutes ago, Strange said:

    Huh? So what. The muon will decay in a few microseconds, even though nothing changes in the meantime. So obviously time passes with no change.

    The universe around it does and eventually the muon as well. Change without time in the Sydney Shoemaker sense doesn't preclude you could have objects that in the presence of change around them retain the same properties (relational/monadic) so that they do not change. Extend your example to a universe without any physical clocks/substantivalist time implied? 

     


  18. 2 hours ago, Strange said:

    If you curve the empty spacetime then you will get gravity. Well, depending how you curve it, I suppose. 

    IF. . . you can have empty spacetime and our substantialist interpretation of general relativity holds water in the possible absence of quantum fields. Or that it holds at all. Map versus terrain issue here? 

    30 minutes ago, Strange said:

    Take the example of a muon then: no internal structure, nothing to change. And yet it still decays after some time.

    Yes, it has the properties that you ascribe to a muon then after some allotted time (certain amount of ticks by physical clocks in nature or in the lab) it changes to have there be other particles with unique relational/monadic properties (mass, charge, spin, etc) but so what we regraded as the muon no longer exists. . . change has occurred due to a difference of properties after a certain number of clock ticks from one of our physical clocks/internal clock has gone by. 

    32 minutes ago, drumbo said:

    Lol muh fallacy. Consider this, if space in quantized, and we know it is, then how could time also not be quantized, since one cannot exist without the other?

    As far as I know we do not happen to know that time is quantized or that there should be a benefit mathematically to experimentally show the improvement of moving from a real number line representation abstractly of change to that of the natural numbers.  


  19. 19 hours ago, Zetetic Zen said:

    Lol. I see plenty of dismissal, ridicule and condemnation but not a sign of any intellectual, scientific refutation of the information AND observational/experimental evidence provided and included in the article. Such as, the ferrocell device revealing that masses and magnets do NOT mutually accelerate towards each other, contrary to your academically endorsed and over popularized conventional theories of EM and gravitation. 

    You may think it's all pseudoscientific technobabble, but i am merely reiterating the works of scientific greats such as Tesla, Faraday, Maxwell, Heaviside, Steinmetz, and others. It is their terminology which i use. It would be unwise to accuse their collective work as pseudoscience merely because you are unfamiliar with their terminology. Without these people we wouldn't even be having this discussion, as we owe to them our entire electrical grid and modern communications system, not excluding the internet.  

    Instead of dismissing new information which challenges your world view as a "conspiracy theory" or "waste of time", why don't you actually try learning something new? It's OK to be wrong sometimes. Accepting that your universities failed you may be the only way science will ever progress from this point, to be fair.

    Paroxysm, props to your family member, they clearly have an open mind and are seeking the truth, you could probably learn quite a lot from them.

    "The scientists of today think deeply instead of clearly. One must be sane to think clearly, but one can think deeply and be quite insane. Today’s scientists have substituted mathematics for experiments, and they wander off through equation after equation, and eventually build a structure which has no relation to reality.

    Einstein’s relativity work is a magnificent mathematical garb which fascinates, dazzles and makes people blind to the underlying errors. The theory is like a beggar clothed in purple whom ignorant people take for a king… its exponents are brilliant men but they are metaphysicists rather than scientists." - N. Tesla

     

    Have a blessed day, Everyone. Wishing you all the best in your journey towards discovery. Just remember that the real obstacle to discovery is not ignorance, but rather the illusion of knowledge.


    Romans 1:22

     

    When you can empirically show with the correct mathematical results (not hidden) the exact perihelion shift that mercury has or derive on approximate scales an inverse square law of gravitation only then would you hold any water. Though, when you say "they do not mutually accelerate towards each other" are you talking about the minute effect of gravitation that would be overcome with magnets (thusly not show up) or that north pole of a magnet won't accelerate to a south pole and vice versa?  It's not that difficult to figure out the force required to keep two magnets apart or have them attract each other, https://en.wikipedia.org/wiki/Force_between_magnets. For closer approaches or more elaborate distributions you would perhaps require numerical simulations to do the work for you. In your ferrocell it looks to be the case that at the center point between the two magnets looks rather unstable (field lines wise) and would have the incident light behave in a similar manner to a sink or source, what about this does mainstream science not get?

    Weird how this comes into contradiction with mainstream scientific models. . . even though for everything we've made strides in technologically we've had to use this knowledge without much issue, 🤨  .


  20. 19 hours ago, studiot said:

    I have never suggested that change and time are not connected in some cases.

    All that I have been saying is that time is not necessary for change.

    Equally Change is not necessary for time.

    Sometimes (pun intended) we monitor our gauges over time and wish to record 'no change' or 'zero change' .

    It's entirely undeniable that certain physical processes occur (in relation to set unit clocks) and what was investigated in Sydney Shoemakers thought experiment was whether time progressed without their being physical processes. What if every object remained spatially the same distance from each other and retained the same properties would we say that it still makes sense to say that some temporal change occurs despite no physical process alerting us to it? Distinct universal slices both previous and future oriented that look physically exactly the same being distinguished in some unknown manner (by what ever is defined ontologically as time substantially here)? 

    I should note again that the thought experiment doesn't rule out nor come into complications with spatial or other change. 


  21. 18 hours ago, Markus Hanke said:

    Thanks, I will need some time to read this paper, before I can formulate a meaningful reply.
    But I don’t really understand where the argument is going, because the thought experiment implies the notion of time without change (which seems trivially true to me), and at the same time it is clear that you can have change without any notion of time. So the relationship between time and change is at best described as a correlation, but it is not causative nor an identity in the ontological sense.

    It's not that it's trivially true only that it conceptually possible whether it really is the case that all physical processes could halt and there still be a sense of time tick along without recourse to any physical thing thats a part of the universe. I wouldn't describe as correlation but rather as an abstract relation between two different but similar (perhaps the same) concepts of time which seems to be abstraction of imperfect physical change and the change of objects themselves which can be rather chaotic but also predictable. Change and time should be purely descriptions of what physical objects/relations/fields do but not what is (ontologically). 

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