Here are some simple examples of 'simultaneity problems' as I see simultaneity defined and discussed wrt SRT. Perhaps there is no problem? Don't be timid here, speak your peace. Please Register or Log in to view the hidden image! When AE defined "relative simultaneity" was he a bit short sighted in what data and analysis he excluded vis a vis what data and analysis was included? GeistkieselPlease Register or Log in to view the hidden image!
James R, Call it what you will. What do you want to do turn this thread into a discussion of whether AE "defined" or "derived" the form of his simultaneity concepts? Didn't you make some references to improper posts such as the one you just published above? But then you're the moderator aren't you? In "Relativity" circa 1915 AE described simultaneity and the "loss" there of. His description was one of pure definition as based on some simple and unanalyzed and underexplained conditions regarding a train moving wrt the embankment. I notice once again that James R, the Great Deflector, is unable to answer a very straight forward post with anything other than irrelevancies. What's the matter with you James, are you too timid, too unsure of yourself, suspecting the worst possible scenario, SRT is has been falsified, to enagge in a discussion with me on the issue presented in my opening thread? Show us what you are made of James, reallhy made of. Show us some scientific inetgrity, objectivity, rational thought, the ability to engage in hypothetical discussions by maintianing a course consistent with the thread under discussion, oh what's the use? Question for James R: If AE's Simultaneity Model goes, so goes the SRT, correct? SRT tells us that what is simultaneous in one frame is not simultaneous in another frame. In fact James R, AE used the structure of the conditions described in the opening thread to definethe lack of simultaneity of photons emitted simultaneous in the stationary frame could not be considered simultaneous in the moving frame, where the observers in the moving frame considerd their frame at rest wrt to the stationary embankment. Well there were no comments from real observers as AE was doing the talking for all of the hypothetical passengers. Question for James R: Please explain any conditions you see why the photons cannot be considered emitted simultaneosly by observers in the stationary and moving frames. The observers in the moving frame recording the time the photons were emitted in the moving frame prove the photons were emitted simultaneously in the moving frame as the clocks in the movng frame at A' and B' were synchronized in the moving frame. So, where does SRT enter the discussion to save itself? If data recorded in the moving frame shows that the lights were emitted simultaneously because the clocks both recorded the same time of emission in the moving frame, why would any obeserver deny the photons were emitted simultaneously there? Remember the AE gedanken in the book referenced? The mere fact that the moving frame recorded the photons coming from the front of the moving train before those recorded from the rear of the train AE tells us the photons were emitted sequentially. Of course, AE has the train assumed at rest wrt the stationary frame, he excludes some real motion, he doesn't tell us that all times of arrival of the light at various points along the trajectory of the train and the stationary embankment are all symmetrical, even for the observers on the moving frame. When the light arrives simultaneously at the midpoint M in the stationary frame this event is also witnessed by passengers on the train. The fact that observers on the train at A' and B' on the train record the times the light was emitted from A' and B' using synchronized clocks, where such data is available to the moving observers the exact instant the final data arrives at her position on the train is not even referred to. Question: May observers in equivalent frames of reference assume their frames are moving wrt the other inertial frame when relative motion of the two inertial frames has been determined? If the answer to the above is in the affirnmative why do we never see cases where SRTists assume the moving frame is actually moving as in train/embankment gedankens? The answer is because SRT would not be needed inm those cases, correct? It seems the practice of using observers that are not only not cognizant of their own motion, but are totally unaware of the fact that they could be moving and that had they adopted the "moving" assumption, even for a few minutes analysis, then the state of ignorance of why the lights arrived sequentially at the moving observers position would evaporate. Certainly no observer is used that have ever observed experiemnts conducted in the stationary frame correct? In a previous thread where light was emitted from the midpoint of clock mirrors on the moving frame there was the SRT claim that the photons arrived simultaneously at the clocks where one was moving toward an oncoming photon the other moving away from the chasing photon.All this contrary to observation by everyone else in the universe. Well if those photons had as SRT expressed, arrived simultaneously at the clocks then how do you explain that the SRT claim that the the photons arrived simultaneously at the moving midpoint of the clocks as observed by the staionary observer? What is simultaneous in one frame is not simultaneous in another frame correct? Isn't this the postulate echoed by the SRT chorus? No absolute time and space, and reality as I hear you collectively humming. Well let me inform you all: You are all off key and, boringly flat. Confusing isn't it james? It is just like a bad dream where you just can't seem to wake up, isn't it? Is SRT becoming more and more like a boomerang that wont work, you know, "a stick"? Geistkiesel Please Register or Log in to view the hidden image!
geistkiesel: Do you understand the difference? Because it is an important one. Fine. I'll leave you to it, and bow out of this thread. It is fairly clear you don't want my input, and I'm not that keen on wasting my time on you anyway. Yes, because the relativity of simultaneity is a derived consequence of the theory of relativity. It isn't some ad hoc addition which Albert added on a whim. I've done so before, many times, geistkiesel. At one stage I even wrote an elegant post, complete with spacetime diagrams, explaining the entire thing in detail. If you can't find that, look it up on the web. There are plenty of good sites which explain it very clearly. The motion of the embankment is as "real" as the motion of the train, geistkiesel. I've really given up trying to explain reference frames to you, since you can't grasp the basics, and without those there is no point in trying to take you further. I suggest that you go away and read an introductory text on special relativity. See if you can fault any of the derivations given there, and then we can have a discussion. Alternatively, you may disagree with one or both of the postulates of special relativity, in which case we can also have a discussion. But right now, you just keep insisting on a Newtonian universe, without even understanding the essential differences between an Einsteinian universe and a Newtonian one, so that your objections to Einstein are implicit in everything you write, rather than explicit. In short, you don't know what you are really arguing. Right now, you're like a man who has only ever eaten an apple, who therefore assumes that apples are the only possible type of fruit. When shown a banana, he denies that it could be a fruit, or, if it is a fruit, claims it is a fraudulent one. You need to broaden your horizons and realise there are more things in heaven and earth than are dreamt of in your philosophy.
James R, Here is a simple arrqangement. Observers A and B on the moving frame (wrt the embankment) measure the arrival of photons emitted simultaneously in the stationary frame. A and B using synchronized clocks in the moving frqame are co-located with the emitted photons when emitted simultaneously in the stationary frame. Under what law of physics do the times become sequential to the observer on the moving frame who was at the midpoint of the emitted photons wrt the embankment when the photons were emitted? If the observer who was at the midpoint of the emitted photons when the photons were emitted assumes he is at rest wrt the embankment and sees the photons arriving from the front then from the rear, how does this observer ignore the data taken by observers on his own moving frame? The observer on the frame who was aty the midpoint when the photons were emitted must claim the photons from B were emitted before the photons from A, which is contrary to data taken nby A and B on the moving frame. The data show the observers assumption of a state of motion "at rest" is shown to be in error by the data. This is too clear a situation to go harping back to what you claimed to have shown me [and others -this is just James R in his "denial mode"]. This is too trivial and basic a question in SRT to avoid by mere posturing. Why not try a new mode of response: analysis of the problem and response to the propblem as satted? Geistkiesel Please Register or Log in to view the hidden image!
geistkiesel: I don't understand this. If A and B are "co-located" with the emitted photons, then the photons don't have any distance to travel to get to A and B, so the elapsed time between emission and reception is zero in both frames. I think I understand what you're saying. You are saying A and B are at either end of the train, and your third observer is in the centre. You're saying that the photons are emitted at the locations of A and B (at the instant they pass the points of emission), simultaneously. And you're asking how the photons can be emitted simultaneously and yet received by the observer in the middle non-simultaneously. The answer is: they can't. So, where did you go wrong? You went wrong because you specified that the emission was simultaneous in the stationary frame (i.e. embankment frame). That means the emission was not simultaneous according to A and B (on the train). And therefore there is no problem with the reception being non-simultaneous by the observer in the middle of the train. If you had specified that the emission should be simultaneous according to A and B, instead, then the reception by the middle observer would have been simultaneous. But then, an observer on the embankment would not have seen the emission as simultaneous (even though reception is still simultaneous in the embankment frame). No. You just made a simple mistake. Better make sure you get your facts right before making accusations like this in the future, don't you think? So, now that I have pointed out your error, I'm sure you'll do me the courtesy of thanking me for the help I've given you. Right?
The photons emitted on the stationary frame are split by half silvered mirrors and each travel the same distance to the observers on the moving frame at A and B as well as the "starting point" of the sources on the stationary frame. No am not saying that. We all know the lights will arrive at the observer that was initially co-located with the midpoint of the sources on the stationary frame as the observer is moving towards one of the sources. I am questioning how the moving observer can conclude that the lights weren't emitted simultaneoulsy in the moving frame if the A and B observers both record the arrival of photons in the moving frame simultaneously as recorded by their clocks? You are invoking special relativity theory here as your answer aren't you? So explain then how SRT can negate the simultaneous arrival of the photonsw in the moving frame when the data (clocks at A and B) shows the converse. Well I did state that the emission was suimultaneous for A and B as well as in the embankment. But here the middle observer would still see the lights arriving sequentially as she is heading toward one of the emitted photons. This cannot be. The given here is that the lights were emitted at both sources simultaneously. Under these condiotions the lights must arrive at the midpoint (stationary frame) at the same time. If the lights were emitted by sources when A and B were co-located with those sources then both frames must necessarily see the lights emitted in their frames simultaneously. Especially when confirmed by the clocks of the observers at A and B on the moving frame. Here the midpoint of A and B i.e. the moving observer, was co-located with the midpoint of the sources of light on the stationary frame at the instant the lights were emitted. Or put the source on the moving frame and conduct the same experiment, the result is the same. The observer on the moving frame will see the lights arriving sequentially in any condition. I see no mistake, simple or otherwise. What accusation did I make? I do thank you for the help you have given me here. However, as you can see I disagree with your analysis that made some errors in reading what I posted. Simply said the lights emitted simultaneously in the stationary and moving frame will always be deemed not simultaneously emitted in the moving frame for the simple reason that the moving observer that was located at the midpoint of the source (whether the source was on the stationary frame or the moving frame)has moved and will always see the lights arriving at her location sequentially. USing this seque4ntial arrival alone is pr3emature conclusion arrived at withjout a complete analysis of the events. However, other observers than the primary observers position on the moving frame can see the photons arriving simultanoeusly at the position where the moving primary observer had been previously located when the lights were emitted. To these observers the lights must have been emitted simultaneously in the moving frame. It seems that SRT has a unique observer that determines the simultaneity, or not, and/or physics of the entire frame, what ever its size or however the observers may be arranged on that moving frame. Seriously, James R, I do appreciate your detailed examination here as opposed to general references to SRT as so many SRTists are wont to do. Bottom line here We are discussing the simultaneous emission of the lights into both frames, not ecessarily the arrival of the lights at the midpoints of the A and B observers. The observers on the moving frame who see the lights arriving at the stationary frame midpoint verify the simultaneous emission of lights in the stationary frame. A and B verify the simultaneous arrival of the lights in the moving frame. Who determines the motion of a moving frame, one unique observer only? Geistkiesel Please Register or Log in to view the hidden image!
Relativity tells us that is impossible, if A and B are moving relative to the embankment. Every individual frame has ONE and only one notion of simultaneity, by definition of what a frame is.
James R, The problem stated that the clock/obervers on the moving frame were co-located with the emitted light in the stationary frame, The clocks on the moving frame must reas the same number as the clocks are synchronized. How can this data be properly discarded? Please show me how this can physically occur. Lets use a mechanical switch triggered by the passing train that emits the lights at the same instant on moving and stationary frame. I am not saying same clock time, merely the same instant at both ends of the train. AE used a gedanken similar to this in "Relativity" pulished 1916. Hed concluded because the observer had been at the midpoint when the lights were emitted at A and B in the stationary frame and because the lights arrived at the position of the primary observer from B before A that the lights must have been emitted sequentially with B emitted first. This of course follows the assumption the train was at rest wrt the embankment. AE gets away with insisting the lights were emitted sequentially when they obviously were emitted simultaneously. Other observers on the train were at the embankment midpoint when the lights arrived there simultaneously. Does the inertioal frame have one primary observer located uniquely on a frame that gives that observer 'equivalence granting' powers? The analysts on the train can determine from the data they have that motion is consistent with the data: their velocity, measured from time at the midpoint to arrival of the beams from B then A. All from the moving frame clocks. What stops them from doing this? Bottom line James R: Is the observer on the train justified in assuming the embankment is at rest and the train moving in these gedankens? Geistkiesel
James R, to remove any ambiguity in our discussion I offer the following: A question of simultaneity. There are two light sources (with clocks synchronized in the embankment) on a train moving with velocity v wrt the embankment. An observer on the train, O’, is located at the midpoint of the lights located on the train at A and B. Just as O‘ is adjacent to M on the embankment the lights flash on the train simultaneously. Question: Will the lights arrive at O’ simultaneously? Please explain. D Does the fact that the clocks at A and B record the emission of the lights in the moving frame at the same instant have any affect on your response? Question: Will the lights arrive simultaneously as seen at M (located within a wavelength of O') by an observer on the embankment? Please explain. Geistkiesel Please Register or Log in to view the hidden image!
A question of simultaneity. There are two light sources on a train moving with velocity v wrt the embankment. An observer on the train, O’, is located at the midpoint of the lights located on the train at A and B A and B . Just as O‘ is adjacent to M on the embankment the lights flash on the train simultaneously. Question: Will the lights arrive at O’ simultaneously? Please explain. Question: Will the lights arrive simultaneously at M on the embankment? Please explain. Quote=James R]I think I understand what you're saying. You are saying A and B are at either end of the train, and your third observer is in the centre. You're saying that the photons are emitted at the locations of A and B (at the instant they pass the points of emission), simultaneously. And you're asking how the photons can be emitted simultaneously and yet received by the observer in the middle non-simultaneously. The answer is: they can't. So, where did you go wrong? [/quote] I didn't go wrong. Then times and distances must be adjusted on the moving frame correct? The observer on the embankment must see the lights travel at the same speed on the moving train (assumed at rest by O’). Therefore, the light from the front of the train will arrive at O’ before the light arrives from the rear of the train as observed from the embankment. Using the definition of simultaneity as defined by AE it is impossible for lights to be measured as emitted equal distances from O’ in the moving train at the same instant. This is so even though the lights were emitted equal distances from the O’ at the same instant on the moving train. Therefore, for AE motion with respect to the embankment is a state of ‘non-simultaneity’: it is impossible for the definition of simultaneous events to occur on inertial platforms moving wrt the embankment. AE defined events as simultaneous if, for instance, lights emitted simultaneously at equal distances from a point M the lights will arrive at M at the same instant. Using AE’s version of ‘simultaneous events’ it is impossible to produce the necessary conditions resulting in simultaneous events on an inertial frame of reference moving wrt the embankment. In order that lights emitted simultaneously from A and B on a moving platform to arrive at O’ (the midpoint of A and B on the moving train) simultaneously, either of the conditions below must occur: a. The distance between O’ and the forward source must extend to match the effective distance of the light arriving from the rear or, b. The distance between O’ and the rear source of light must contract to match the effective distance of the light arriving from the front of the train. c. The light from the rear of the train must speed up to > C in order the lights arrive at O’ at the same instant or, d. The light from the front of the train must be < C in order that the lights arrive at O’ at the same instant or, e. Some combination of a – d above, which because of symmetry considerations are impossible physical conditions to achieve. f. Whatever version of the constancy of light one chooses to adopt, even the AE version, simultaneity as a physical result of light motion, is impossible to achieve on inertial reference frames moving wrt the embankment. To those having problems resolving the above with learned SR postulates consider that the light emitted and moving internally wrt the moving inertial frame is oblivious to the very existence of the moving frame. The observer on the train can choose the light emitted on the train or the embankment from which to measure whether the lights arrive at O’ at the same instant, the result is the same. If the lights emitted at the same instant in the moving inertial frame then by a clear physical recognition of two events occurring at the same instant, tautologically a simultaneous events is manifest. However, using AE’s definition that simultaneity requires the lights to arrive at O’ at the same instant the conditions of the definition of simultaneity can never be met for an inertial frame moving wrt the embankment. From the above the SR concept of equivalent inertial frames is patently erroneous. You are referring to SR postulates. Can you prove these postulates work as you describe? Or is it as matter of trust or something? No mistake JR, see above. Geistkiesel Please Register or Log in to view the hidden image!
geistkiesel: Simultaneously according to who? The train observer, or the embankment observer? (This is the whole point of the discussion, remember?) For the following answers, I will assume they flash simultaneously for the train observer. Yes. The observer is half way between the two points. Light travels an equal distance, at the same speed, in both directions from A and B to O', so O' receives the light from both directions simultaneously. Yes. That is the initial assumption I am making. If A and B didn't record the emission as simultaneous, then O' would not receive the light simultaneously. No, the light won't arrive simultaneously at M, because although it was emitted at equal distances from M and travels at the same speed in both directions towards M, it was not emitted simultaneously at the two emission points, according to the embankment observer.
Simultaneous as measured by the clocks at A and B on the moving frame. This data is available to the observers on the moving frame as well as the embankment observer. Will the lights arrive at the Midpoint of the sources of the light on the moving frame as seen by the observers on the moving frame? The distance from M on the embankment to the A and B sources when the light was emitted is identical. Therefore, the light must arrive at the midpoint on the embankment simultaneously. M and O' were at the same location when the lights were emitted on the moving frame. How can you arrive at the conclusion that the lights arrive at the midpoint of A and B on the moving frame? The light coming from the front has a shorter distance to travel than the light from the rear of the train. The lights cannot arrive at the midpoint of the moving frame if they are emitted simultaneously from A and B where the observer is at the midpoint of the lights in the moving frame. However, the embankment observer sees the light traveling at the same speed as if emitted in the embankment, therefore the lights will arrive at M the enmbankment simultaneously. Remember, M and O' were at the same point when the lights were emitted on the moving frame. Yes the lights was emitted at the two emission points simultaneosuly according to the embankment observer. M and O' were co-located when the lights were emitted. The problem said the lights were emitted at A and B when the midpoint of the A and B lights on the moving frame were at M on the embankment. You have a serious simultaneity Please Register or Log in to view the hidden image! problem here and merely stating that what is simultaneous in one frame is not simultaneous in the other doesn't answer the ambiguity in your responses. How do yo0u explain that the light has different distances to travel to reach the midpoint of the moving train when emitted simultaneously in the moving frame? Geistkiesel Please Register or Log in to view the hidden image!
Your last sentence here makes absolutely no sense to me . Did you mean to say what you said? If the light was emitted in the embankment at equal distances from M simultaneously, the lights must arrive at simultaneously. Actually I did say the lights were emitted simultaneously in the moving frame. But let us continue. A and B in the moving frame emit light simultaneously in the moving frame. A' and B' are on the embankment where A' is co-located with A and B' co-located with B at the instant the lights were emitted at A and B simultaneously as measured by the synchronized clocks at A and B. If I understand you correctly, the lights will arrive at the midpoint of A and B on the moving frame simultaneously. As the lights in the moving frame emitted light into clocked points at A' and B' on the embankment, the times on the two synchronized embankment clocks must be identical. The distance from A' and B' to M on the embankment are identical hence the lights arrive at M simultaneously. As the lights were emitted simultaneously in the moving frame also, according to SR the lights must arrive at the midpoint of the A and B enmitters simultaneously also. I realize I have just described a conditon prohibited by SR, but how do you resolve the conflict? If the moving observer assumes she is at rest how do the times and distances the light has to travel in the moving frame (which is the same distance the lights travel in the embankment) dilate and/or contract when the symmetry of the two halves of the moving frame must all dilate or contract the same? Geistkiesel Please Register or Log in to view the hidden image!
geistkiesel: You're making unwarranted assumptions, and ignoring the very important fact that the speed of light is the same in both frames, in both directions. Only if it was emitted from A and B simultaneously. In the embankment frame is was not. Agreed. No. In the train frame, the light has equal distances to travel from the front or rear of the train to the middle. You are attempting to work in the embankment frame to calculate what the train observer sees, and that doesn't work. Here, you ignore the fact that in the train frame, light travels at c in both directions (and NOT c+v and c-v, where v is the train's speed - which is what would happen in a Newtonian universe). According to O', A and B are at equal distances from O'. Light emitted simultaneously from A and B travels at speed c in the train frame, and therefore covers the same distance in the same time, reaching O' simultaneously from both directions. Only if the emission was simultaneous in that frame - and it wasn't. Yes, I agree. You're assuming that without proof. And, in fact, we can use relativity to prove that your assumption is incorrect. There's no ambiguity in my responses. I'm just telling you what relativity says about the situation. You have a two options: 1. Accept what relativity says. 2. Reject the reality of relativity in favour of some other theory. 3. Assert that I have not given you a correct solution according to relativity. Since I'm sure (1) is not an option for you, you are left with (2) or (3). If you want (3), then you need to provide a mathematical derivation using the principles of relativity which shows I am wrong. If (2), you need to provide an alternative theory. Newtonian mechanics, as we know, is not sufficient, since actual experiments prove it is incorrect. So, you'll need some other new theory. Do you have one?
No I agree 100% that the speed of light is the same in both frames in both directions. This is what I am talking about. Forget for a moment the arrival of the lights at the O' or M location. If you grant that the clocks monitoring the emission of the light in the moving and embankment frame are synchronized in their respective frames and further that the A and B sources/clocks are perfectly aligned with he A' and B' counter parts in the embankment and say the A'A and B'B distance are an 'x-ray' wave length apart and the light emitted is visible. The light emitted from A and B then arrive in the embankment no longer than it takes the light to traverse the distance separating A'A etc. If we do nothing else except look at the clocks in both frames and we will see that the A' and B' clocks agree and the A and B clocks agree as to the time of emission; or better we can say that the emission sets all four clocks to zero. With errors that are insignificant to Newtonian and Special Relativity Mechanics. I would gather this data take a good look at it at it and come to the unambiguous conclusion that the lights were emitted simultaneously in both inertial frames. Further: Now if, as you have said in no uncertain terms thagt the speed of light is the same in both frames and that the embankment observer will be unable to distnguish between the lights traveling toward M in the embankment and the lights traveling toward O' in the moving frame at least to the observed speed of light. The race of the lights aill be a tie as observed by the embankment observer. (I still haven't invoked any SRT here, but believe me I believe your interpretation of SRT handling of the current situation.) Unambiguopusly the lights were emitted at the same measured (within experimental error) time in both inertial frames. The embankment observer sees a tie of the light race and concludes the lights arrive at M simultaneously. I say this from your statements that the speed of light is impervious to the motion of the moving train. I am interpreting you as saying effectively that we can remove the train from the equation as far as the embankment observer is concerned. So SRT tells us that the distances from A to O and B to O are identical. I can go along with the frame contraction in the A to O section in the rear half of the train which would shorten the distance the light has to travel to reach O, but I do not see how the frame contraction can help the light heading for the front of the train where O is in a collision course with the B to O light. Intuitively this says that if the frame contraction of the front half is symmetrical with the contraction in the rear half that the light will arrive from B before the light arrives from the rear, or from A. The speed of light is not an issue once we use frame contraction that tells us through SRT that the distances are the same. I am seeing this from the moving frame. In other words, the Observer in the midpoint of A and B will see the times of emission of the light in the moving frame when the light arrives at O assuming the times are embedded in the light signal itself. Again I realize the fndamental SRT statement that re simultaneity that what is simultaneous in one frame is not simultaneous in another. How does SRT relieve me of my conclusion that sonething is ambiguous here? I tried to avoid that and I thought I had with the last statements made. So lets us focus enmtirely on the moving observer and the train. She sees only one event from her personal observation. She sees as SRT tells us, the lights arriving at her position simultaneously, which would verify, I suppose, her assumption that the train is at rest wrt the embankment. I assume also that she will see the race of the lights as did the embankment observer end in a dead heat, a tie? What I do not see is the moving frame effectively being independent of the motion of the emitted light. To say the words, "The speed of light is the same for all obserbvers regardless of the relative speed of all moving inertial frames". I may have this less than absolutely perfect but it means that all moving observers will measure the speed of light as C. In other words the relative speed of frame and photon is always measured as C. I question the statement as being consistent with the postulate of light that assures us that the speed of light is independent from the speed of the source of light. Yet here we have a very definite dependence of light and inertial frame speed established and cast in the concrete of SRT. Is the postulate of light as used by SRT concistent with the statement that the speed of light is impervious to the motion of all inertial frames? That if we measure the speed of light emitted on a moving platform that unlike the bullet fired on the moving train the light does not absorb any motion of the moving platform? If this is true then is it not also true that when we measure the speed of light emitted on the inertial frame that we must subtract the motion of the train from the equation when measuring the realtive speed of tran and photon in order to guarantee that the Vct, the velocity of light wrt the train is really Vct = Vce - Vte, or that the speed of light wrt the tran is the speed of light wrt the embankment, the 'vacua', minus the speed of the tran wrt the embankment. So when we measure, as did AE, the speed of light wrt the embankment is equal to the speed of the train wrt the embankment plus the speed og light wrt the train Vct, and conclude as did AE that Vce - Vte = Vct, which is less than the speed of light wrt the vacua we can recognize the need for the subtraction mentioned above? I am asking, should not AE have merely subtracted the speed of the train wrt the embankment from Vce? Or Vct = Vce - Vte(?) such that Vce = Vte + Vce - Vte?. Not my Newtonian universe. I would simply subtract the speed of the train wrt the "relative motion of frame and photon" and conclude that the frame and the light are completely independent of each other wrt their respective speeds. Therefore whether the observer on the train Measures the speed of light as C is totally insignificant. The observer on the train can just as well use the light moving in the embankment in arriving at conclusions that the light moves equal distances in the moving frame regardless of direction of motion. The light moving from the rear in the embankment then, (or the moving frame) will arrive at M in the embankment, but will arrive at O later and this says nothing about the speed of light measured less than C in any frame of reference. I agree this is what SRT tells us. But then SRT is imposing a dependence on the speed of light to the moving frame based on what the the moving observer sees, correct? I refer you to posts that have asserted that when light is emitted and the phsical source is in motion, that no observer can properly claim that the point the light was emitted follows the motion of the physical source of the light as this imposes a direct dependence of the speed of light on the speed of the source as "seen" by the observer. The moving observer is seeing an illusion if she claims the physical point of emission is stationary wrt the point the light was emitted. The moving frame moves away from the emitted light at A as it heads to the observer (or sub-observer stationed at A) gazing at the physical point the on the frame from which the light was emitted. Similarly to the observer at the front of the train also gazing at the physical emnission point. The obserbver in the midpoint of A and B has moved away from M (which she sees as M moving away from her) and what must she see then? The lights arriving at M simultaneously and at her position sequentually. Then she concludes the light was not emitted in her frame of reference simultaneously as belied by the sub-observers at A and B who might "see" consistently with O, but the times on the synchronized clocks will erase the illusion of her inertial frame being at rest wrt the embankment. ' How does the inability to distinguish any difference in when the light was emitted in either frame from direct measurements of the "zeroed clocks" in both frames affect SRT? Or better, let us trigger the emission of the light from the moving frame by mechanical switches located within the x-ray wave length of the A and A' and B and B' clocks on theeh embankment and the clock/emitters on the moving frame. Do you not see an ambiguity here? Motion of the frame ahs a very definite imposition and deopendence on the speed of light, notwithstanding the fact that the speed of light is constant as measured from all frames of reference. It does no harm to any postulagte of light to say that for light emmitted at A arrives at a point located say ct ahead of the A point on the moving train and thagt this point at ct is vt removed from where the A point was locagted when the light was emitted. In other words to say that C - V is the difference in the speed of light and the speed of the train does not decrease the measurement of the speed of light and especially so when all we are measuring is how much faster is the speed of light than the train motion wrt the embankment. See my discussion above regarding the emission of the lights in the conditions decribed. I am not disputing what relativity has to say, but I would contest that relativity is "proof" of what it asserts. OK, I revise my statement to assert that relativity as generally understood is erroneous for the reasons I discussed above. I do not assert your assesment of relativity is wrong. Your statement regarding 1 is correct. I have never asserted the truth in Newtionian Mechanics as understood even by the main stream dissident faction. I thought you may have guessed that by now. See above for alternative dynamics of the relative velocity of frame and photon. Geistkiesel Please Register or Log in to view the hidden image!
geistkiesel: Ok, so let's see where we're at now. Can you please answer the following questions: 1. Do you agree that my description of what the special theory of relativity says is correct? (Note: I am not asking whether you believe special relativity itself is correct.) 2. Do you agree that in Newtonian physics, the speed of light would NOT be the same in the train and embankment frames? 3. Do you think that the speed of light in the train and embankment frames will be the same in each frame? 4. Do you think that the laws of physics would take the same forms in both the train and embankment frame? For example, if I calculate the force on an object in the embankment frame, and find that F=ma applies, will F'=m'a' also apply in the train frame, even though F',m' and a' may differ from F,m and a? OR will I have to replace the equation by something else, such as F'=m'a' + other terms (maybe depending on v)? 5. Do you believe that Newtonian physics is correct? 6. If the answer to (5) is "No", then please give a set of postulates which you do believe in, so that we can start analysing the problem from your point of view.
From your input here, yes. No, it would be the same. From whjat I gather there is a difference of expression, not always clearly stated. Some would consider the measurement of C - V or C + V as examples of lack of the constancy of the speed of light. Yes. I also believe that the relative velocity of frame and photon in general is c - v, not c, which is not a statement slowing the speed of light by the amount of v. The terms is a relative speed of frame wrt photon and vice versus. I haven't delved that deeply into it but it seems reasonable that the physics would take the same general form. However, if discovering variations in form as in the slavish adherence to form as expressed in relativity I wouldn't hesitate to offer exceptions to golden rules. However, relative velocities would differ in each inertial frame and from this I have some reservations. For instance, regarding the energy term, E = 1/2 mv<sup>2</sup> where the frame energies would differ might need some adjustments. I do see some variations of Newtonian physics as presently understood, and practiced, which I will outline. The observed affect of accelerations to high speeds is not velocity dependent, rather velocity measures the state of energy of the accelerated paricle, which is not a statement saying I believe the particle mass increases. I cannot accept that velocity, a forceless expression, can have any physical effect especially to the degree claimed by relativity, a nmeasure of energy state, yes. Some of it. Newton's claim that "inertia" was an intrinsic attribute of matter, for instance, such as weight, size, etc I don't buy. There is more, but basically I would have to say yes, if you insist on an answer. Since you keep using 'Newtonian' and 'Newton' I do believe that IN is history's most prolific and successful plagarist; so when you say 'Newton', I really don't know who you are discussng. I am not a scientific philospher and I only engage in this forum for the reasons you can decipher yourself. I understand your question and I will respond, but it wont be what you are expecting. It certanly will not be in the form of neat postulates we see in relativity. Geistkiesel Please Register or Log in to view the hidden image!
geistkiesel: Thanks for the clear response. Most physicists would regard the measurement of the speed of light in the train frame as c+v or c-v to indicate that the speed of light is different in that frame. I suspect this may be one reason you and some of the other people here so often find yourselves talking at cross purposes. What you seem to be imagining is that light travels in some medium (call it an "aether" if you like) in which it has the speed c. If an observer, like the train, moves at speed v relative to that medium, then the observer will measure the speed of light as being v+c or v-c, even though the "real" speed of light hasn't changed, because the only "real" speed is the speed with respect to the aether. Is that a fair description of what you believe? Ok. This is really a topic for another thread, if you want to discuss it.
