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My question is asking for evaluation of a new concept or paradigm within the framework of the current mainstream physics understanding of Relativity. Specifically, that concept or paradigm being that, “it seems we do not seem to actually observe ourselves or anything else heading into a future, or leaving a temporal past behind us, or observe that a future is constantly arriving, or a past receding, or a thing called time passing, Therefore it may be possible that the universe is just as it actually appears to be, I.e. Just filled with matter(/energy), just, existing, changing, moving and interacting at various rates in all directions".

Evaluating this concept within Relativity; in Einstein's On the Electrodynamics of Moving Bodies section 1, it is stated (para 3) that...

If we wish to describe the motion of a material point, we give the values of its co-ordinates as functions of the time.

But the example given only says...

If, for instance, I say, “That train arrives here at 7 o'clock,” I mean something like this: “The pointing of the small hand of my watch to 7 and the arrival of the train are simultaneous events.”

So, in fact it seems the motion of a material point (the train), is only actually compared to the location and/or motion of another material point (a small rotating hand), but the motion of this second material point is just called “time”.

i.e. It seems logically no reason is given why we should assume that the train, and the pointer or “hand” are not just constantly existing, and moving or not, somewhere. That is, no reason is cited to assume the rotating hand is not just a rotating hand, or that a thing called time actually is passing, or that anything is other than existing and moving “simultaneously” ( to use a possibly redundant word).

However, as Relativity (imo legitimately) does show that moving objects are changing within themselves more slowly, it seems to also infer from this that,

we cannot attach any absolute signification to the concept of simultaneity

Suggesting there might be genuine discrepancies about “simultaneity”, or even the order of events (for observers in different locations, moving at relative speed etc).

But, extra to just “calling” the rotation of a hand on a dial “time”, the passage of a thing called “time”, and the concept of non-simultaneity being legitimate (i.e. the idea there are different times), does not seem to actually be demonstrated in the paper.

So, why should we accept the idea...

we cannot attach any absolute signification to the concept of simultaneity,

If it has not been shown that anything is other than "simultaneous" - (or rather "just happening"), rather than just considering that everything, may just always be somewhere, doing something, at relativistically dilated rates, but still just somewhere, “now”?

Kyle Kanos
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MattMars
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    Given the level of your confusion, may I suggest a reset of your efforts into learning physics, by learning it right from the start? I think you would greatly profit from taking an experimental physics class that can convey a hands-on meaning of what "reality" means from a scientific perspective. – CuriousOne Oct 14 '14 at 14:11
  • This is a variation on this closed question: http://physics.stackexchange.com/questions/139342/where-in-einstein-s-on-the-electrodynamics-of-moving-bodies-relativity-is as to the new question on the relativity of simultaneity, I will suggest the duplicates – Void Oct 14 '14 at 16:14
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    I'm not convinced that's a duplicate, at least partly because I'm not sure the OP is clear what they're asking. – John Rennie Oct 14 '14 at 16:42
  • Hi @CuriousOne, Thank you, but your response doesn’t actually address the question, (if you can recommend a particular book or online experimental course, I’ll take a look, but I haven’t found many problems with my current research material http://goo.gl/Qvqug9). So we can be sure you are looking at my question with an open mind, and not just assumed i am confused. would you please cut/paste the specific part of it that made you think so, so I'm not addressing just a vague opinion. – MattMars Oct 14 '14 at 23:39
  • Thank you @void that question is closed for what seem to be invalid reasons, i.e. the suggestion Relativity is not mainstream physics, and, even though it is “a question that proposes a new concept or paradigm, but asks for evaluation of that concept within the framework of current (mainstream) physics (is OK)”. Hence the new question. I sincerely appreciate the answers given, but with respect they each seem to dodge the main point of my actual question, in essence, “why is it valid to assume ‘time’, with all its implications shoud be assumed in Relativity, rather than just motion” – MattMars Oct 15 '14 at 00:10
  • @void (re question closed, but perhaps not correctly). Answer 1, says “Relativity does describe facts properly”, but it seems not to, i.e. it describes the fact things can be moving, as “time”, and concludes issues with “simuntainiety”, where only motion, and dilated rates of change “now” seem to actually be observed. i.e it does not seem to be a fact that anything may be happening "non-simultaneously", and the word "simultaneity" suggests there is much more to "time" than it being just another word for motion. (Which seems not to be factually correct). – MattMars Oct 15 '14 at 00:16
  • @MattMars: My question does is answering your existential problems. Learn physics the right way and your confusion will go away. – CuriousOne Oct 15 '14 at 00:23

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The "relativity of simultaneity" is not a statement about what "exists"--that is a matter for philosophy--but just about the fact that the laws of physics obey the same equations in all the inertial coordinate systems related to one another by the Lorentz transformation, which dictates that different inertial systems define simultaneity differently (i.e. two events that are both assigned the same t-coordinate in one system are assigned different t-coordinates in another). Therefore, there can be no experimental basis for picking out a preferred definition of simultaneity--if two experimenters are inside windowless rooms moving inertially relative to one another (in deep space far from any source of gravity), no experiment they can do will allow them to determine their velocity relative to any sort of preferred frame with a preferred definition of simultaneity. If you want to believe that there is some "true" definition of simultaneity (i.e. you want to endorse the philosophy of presentism) but that it is a purely metaphysical matter that can't be determined by any possible experiment, you're free to do so without contradicting anything in the purely physical theory of relativity.

Hypnosifl
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  • Hi @Hypnosifl, much appreciated, As a working basis to avoid diversionary "metaphysics" I`ll take it that people and their computers probably "exist". But "things" like the "tooth fairy" probably don't. from there i would suggest matter seems to exist and be able to move. The paradigm im testing against the the framework of current (mainstream) physics is, "Is SR's statement 'we cannot attach any absolute signification to the concept of simultaneity", valid?", given SR implies issues with "simultaneity", but does not show why we should assume there is anything other than movement "now". – MattMars Oct 14 '14 at 23:50
  • Hi @Hypnosifl, re your answer. "the Lorentz transformation, ... dictates that different inertial systems define simultaneity differently" is understood. My question is: is there any reason why the idea of "simultaneity" needs to be defined, if all we don't actually seem to detect "time" or "different times" in our most basic observations, and If Lorentz's and Einstein's writings perhaps wrongly jump to the conclusion that a "clock", extra to just motion, also indicates the passing of "time". i.e. is it actually redundant and over complex, to suggest that anything is not just happening "now" – MattMars Oct 14 '14 at 23:56
  • Hi @Hypnosifl, re "Presentism", that "[in a]list of all the things that exist...there would be not a single non-present object on the list. Thus you would be on the list, but neither Socrates nor any future Martian outposts". This paradigm is not what i am testing against Relativity. I'm asking, given that all we seem to see is matter, here, moving and interacting, is that all that is needed for our theories to make sense. I suggest that all of the matter that makes up "Socrates", or a possible "martian outpost" seems to always just exist, and be somewhere, existing and changing formation. – MattMars Oct 15 '14 at 00:07
  • ps @Hypnosifl et al, Please don't think i'm being obtuse in my replies, it's hard to be politely formal with such a character restriction, and reply in reasonable detail to issues on such a tricky subject. Also please note I am completely aware that the paradigm i am testing against Relativity, Lorentz, etc may be wrong, I'm not just blindly insisting otherwise, just trying to test it thoroughly becasue if it accommodates yet simplifies the essence of relativity, legitimately eliminating concepts of past, future, and blocktime etc then occam's razor suggests it may be worth considering. M.M. – MattMars Oct 15 '14 at 00:32
  • @MattMars - 'is SR's statement 'we cannot attach any absolute signification to the concept of simultaneity", valid?' Well, I would say the statement is about measurable physical "significance". Do you agree or disagree that there is no experimental procedure to determine whether two events are simultaneous in any objective frame-independent sense? – Hypnosifl Oct 15 '14 at 04:08
  • @MattMars - ' If Lorentz's and Einstein's writings perhaps wrongly jump to the conclusion that a "clock", extra to just motion, also indicates the passing of "time"' I have no idea what you mean here--you talk as though there were some widely-understood meaning to the word "time" other than mutual agreement between clocks (and processes that happen at predictable clock rates), and that Einstein/Lorentz were using this mutual agreement to argue for this other meaning, but you never spell out what the other meaning is supposed to be. – Hypnosifl Oct 15 '14 at 04:14
  • @MattMars - As for the philosophical notion of presentism, I'm not sure you're understanding the concept correctly--do you think that Socrates as a living individual in ancient Greece does not "exist", even if "all of the matter that makes up Socrates" exists? If you say the living individual in ancient Greece does not exist, only the matter that made up his body in its form "now" exists (which presupposes an objective truth about which events are happening 'now'), then you are endorsing presentism. But again this is a philosophical matter, relativity says nothing about what "exists". – Hypnosifl Oct 15 '14 at 04:22
  • Hi @Hypnosifl,Thank you for your replies, I`ll digest them and answer your questions etc. This video may better explain the possibility I am exploring as applied to an apparent "temporal paradox". "The Worm hole, billiard ball paradox, explored, possibly, Timelessly. (re Paul Davies- New scientist article)". https://www.youtube.com/watch?v=Wc5cRGOGIEU M.M. – MattMars Oct 15 '14 at 17:36
  • Hi @Hypnosifl, Re “Do you agree or disagree that there is no experimental procedure to determine whether two events are simultaneous in any objective frame-independent sense?”, This is kind of my point. I agree with Galilean invariance, e.g. “two experimenters are inside windowless rooms moving ” etc, cannot tell their relative velocity... or where the location of another moving/rotating hand on a dial is. Hence I`m asking "is it legitimate to just call motion 'time' ", such that the suggestion things are happening at different "times" (ie non-simultaneous) has any meaning... – MattMars Oct 16 '14 at 13:47
  • ... So i`m suggesting that unless someone can show some reason to suggest things are not just existing and moving then questions like “Do you agree or disagree that there is no experimental procedure to determine whether two events are simultaneous in any objective frame-independent sense?” may be invalid, becasue of the use of the word simultaneous, which only has meaning if there is evidence, rather than just feelings or ideas, or claims it is axiomatic that a thing called time exists... – MattMars Oct 16 '14 at 13:52
  • ... re If you say the living individual in ancient Greece does not exist, only the matter that made up his body in its form "now" exists... then you are endorsing presentism. With respect no, this ultimately comes down to a related question, which is "IS there a 'temporal past' ?". If there is no temporal past, then there is no temporal past, and instead we only have patterns in our minds that we talk about as being about 'the temporal past'. e.g. even the "thought" or "idea" of "a living individual not existing" is here now. But that's not a discussion for this site. M.M. – MattMars Oct 16 '14 at 13:56
  • @MattMars -- "Simultaneity" does not say that "a thing called time exists", I've told you that physics makes no claims about the "existence" of anything whatsoever, it's just about making predictions about well-defined experiments. Simultaneity is defined to be coordinate-dependent, to say that two events are simultaneous in some coordinate system just means they are assigned the same t-coordinates in that system. And t-coordinates are defined in terms of local readings on a set of clocks that can be "synchronized" according to any arbitrary well-defined experimental procedure. – Hypnosifl Oct 16 '14 at 15:51
  • @MattMars - for example, one "synchronization" procedure would be to set the clocks to the same reading when they are next to each other, then move them apart at a very slow relative velocity to different locations on a grid of spatial coordinates. Another would be to set off a flash of light at the midpoint between them and set them to show the same reading when the light from the flash struck them. But you are free to use "weird" definitions like setting them to different readings when they're next to each other and moving apart--this just results in a different type of coordinate system. – Hypnosifl Oct 16 '14 at 15:55
  • @MattMars - once you have laid out clocks at different locations, "synchronized" in any arbitrary way you like, "simultaneity" in the coordinate system defined by these clocks just means "same clock readings on the clock right next to an event". So if you take a picture of one balloon popping showing the clock next to it reading 35 seconds, and you take a picture of another balloon popping showing the clock next to that one also read 35 seconds, then you say both balloons popped at t=35 seconds. – Hypnosifl Oct 16 '14 at 15:58
  • @MattMars - The "time" coordinate for a given event is just defined in terms the local clock reading next to the event, on a collection of clocks associated with the coordinate system in question. There is no pre-existing notion of "time" such that different events having different clock readings next to them is "evidence" of this pre-existing idea called "time", it's purely a definition. – Hypnosifl Oct 16 '14 at 16:03
  • @MattMars - I still am not sure what you mean when you talk about the need for "evidence" for time, BTW--you never addressed this earlier comment: 'I have no idea what you mean here--you talk as though there were some widely-understood meaning to the word "time" other than mutual agreement between clocks (and processes that happen at predictable clock rates), and that Einstein/Lorentz were using this mutual agreement to argue for this other meaning, but you never spell out what the other meaning is supposed to be.' – Hypnosifl Oct 16 '14 at 16:05
  • @MattMars - Anyway, once it is understood that "time" means nothing more than readings on some set of clocks that have been synchronized according to some well-defined procedure, for two events to be "simultaneous" in some coordinate system just means both have the same t-coordinate (local clock reading) in that system, like the two popping balloons in my example above. – Hypnosifl Oct 16 '14 at 16:09
  • @MattMars - In an inertial coordinate system, all the clocks must be moving inertially and at rest relative to each other, and they can be "synchronized" either by setting them to the same reading when they're next to each other and moving them at a very slow relative velocity to their assigned position in the spatial coordinate grid, or by using light signals, like the method I mentioned where a flash is set off at the midpoint between two clocks and they are both set to the same reading when the light from the flash strikes each one. – Hypnosifl Oct 16 '14 at 16:11
  • @MattMars - Now say we have two experimenters in windowless rooms moving inertially, with a relative velocity between them. Suppose both used the "set them the same reading when next to each other and move them apart very slowly" to synchronize clocks at different ends of their labs. Then if the walls were removed and the clocks of each experimenter were compared as they passed by one another, classical physics says their clocks would agree about simultaneity. – Hypnosifl Oct 16 '14 at 16:16
  • @MattMars - For example, if two balloon-poppings were next to clocks A and B of experimenter 1 and both clocks showed the same reading in a photo taken when a balloon popped right next to them, then if these same balloon-poppings were also right next to clocks C and D of experimenter 2, C and D would show the same readings as one another in photos too. But relativity says the two sets of clocks will not agree about simultaneity--if one pair shows the same reading, the other pair shows different readings for the same two balloon-poppings. – Hypnosifl Oct 16 '14 at 16:19
  • @MattMars - that's all the "relativity of simultaneity" means--that no matter what method the experimenters use to define "synchronization" for their own set of clocks inside a windowless room, there's no well-defined procedure they can use that will lead their clocks to agree about simultaneity. – Hypnosifl Oct 16 '14 at 16:24
  • @MattMars - If there was some experiment they could do in the room that would give them different answers for their velocity relative to some absolute frame, they could use that information to make sure their definition of simultaneity agreed with that of an experimenter who uses some simple method to synchronize his clocks when he is at rest in this frame (like the moving-apart-slowly method), but because all experiments give identical results in windowless rooms, there's no such procedure that will lead them to agree on any "preferred" definition of simultaneity. – Hypnosifl Oct 16 '14 at 16:28
  • @MattMars - Note that although the idea that all experimenters will get the same results in windowless inertial rooms is similar to Galilei-invariance, it's different because if different inertial observers construct their coordinate systems using a grid of rigid rulers and the slowly-moved-apart clock synchronization method, classical physics predicts the coordinate systems of different observers will be related by the Galilei transformation, relativity by the Lorentz transform. – Hypnosifl Oct 16 '14 at 16:33
  • @MattMars - If coordinate systems constructed in this way were related by the Galilei transform, then all inertial coordinate systems would agree about simultaneity, and if something had a speed of c in one system, then its speed in a different inertial coordinate system would not be c. Relativity predicts that if different observers construct their systems this way, then if something is moving at c in one system it'll also be moving at c in another, and the systems disagree on simultaneity. – Hypnosifl Oct 16 '14 at 16:39
  • @MattMars - So to predict the laws of physics will be "Galilei-invariant" is different than to predict they will be "Lorentz-invariant", although both involve the idea that experimenters in windowless rooms moving inertially will see identical results of any experiment they do while the room is sealed. You said before 'I agree with Galilean invariance, e.g. “two experimenters are inside windowless rooms moving ” etc, cannot tell their relative velocity...' -- can I assume that now that I've made this distinction clear, you would say you have no reason to doubt Lorentz-invariance? – Hypnosifl Oct 16 '14 at 16:43
  • Hi @Hypnosifl thank you very much for that, As i say i researched these (http://goo.gl/Qvqug9 ) and other works for my own book, but the refresher re Galileo, Lorentz + Relativity is appreciated. I'm going down the pub now, but i have printed your comments off and will read them carefully, and reply (addressing the missed question etc). thanks again MM.(ps if you do check out one of the videos it might give you a clearer understanding as to why im asking my relatively simple question here) https://www.youtube.com/watch?v=ii3gxxn2reA ("Dr WHO" is just the platform Prof Cox used for his lecture) – MattMars Oct 17 '14 at 17:47