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My understanding of Space, Time and spacetime

  1. Oct 16, 2011 #1
    My understanding of Space, Time and "spacetime"

    In thinking about time I have developed the (easy) realization that whenever we indicate a duration we are comparing two spatial changes. I believe it was Einstein himself who pronounced words the effect of time being inexorably tied to space and not having an autonomous existence. This I interpret not in the sense that spacetime is a single entity and certainly not a fourth dimension, or a flow but rather that time is a local property of space.
    By that I mean to say that the rate at which natural phenomena (atomic clocks ticking, cells dividing...) occur must ultimately be tied to spatial effects only.
    It follows that everything that has been observed to give rise to time dilation must be inducing distortions in the three dimensional space. The effects of gravitation and the equivalent inertial acceleration are in all likelihood themselves, the manifestations of these distortions.

    What are your thoughts? What the counter arguments?
     
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  3. Oct 16, 2011 #2

    Bill_K

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    Re: My understanding of Space, Time and "spacetime"

    halix, It often happens that a student new to physics finds special relativity difficult to understand, and has a "revelation" that the theory is wrong, and believes he has developed an insight that 100 years of physicists have unaccountably overlooked. You'll probably have the same opinion of quantum mechanics when you come to it. You'll have more success if you just try to learn physics at first, and not expect to revolutionize it.
     
  4. Oct 16, 2011 #3

    ghwellsjr

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    Re: My understanding of Space, Time and "spacetime"

    There is no spatial distortion in Special Relativity and yet there is time dilation. The only distortion is in your thinking. You need to straighten out your thinking and learn about relativity, instead of promoting your personal, private, theory about relativity. It's against the rules here and will likely get you banned if you persist.

    I strongly suggest that you do a lot of reading on this forum until you can learn about relativity, especially Special Relativity, which really is so much easier to understand than General Relativity, since you like easy.
     
  5. Oct 16, 2011 #4
    Re: My understanding of Space, Time and "spacetime"

    halix, I agree with you. I think the objections you have received so far is because you're not using the "right" terminology to express your ideas.

    The Lorentz ether theory is experimentally indistinguishable from special relativity. Ether or not, there is a structure to space, the distortions in which GR "computes". These distortions manifest as time dilation or length contraction, because the physical processes take place in space. In my view, you're saying the same thing as GR. However, SR and GR treat space as "empty" without clarifying what it is exactly that is being distorted, nor the exact physical mechanism of how these distortions appear. Current ether theories do not give it either, but somehow they "make more sense", maybe because they do not treat space as "empty".
     
  6. Oct 16, 2011 #5

    ghwellsjr

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    Re: My understanding of Space, Time and "spacetime"

    Spacie, in LET there is no distortion of space, just like in SR. Halix said that all time dilation is caused by a distortion of space. How do you see your comments as agreeing with halix?
     
  7. Oct 16, 2011 #6
    Re: My understanding of Space, Time and "spacetime"

    While you are sitting still, look at your watch. After a while, look again. The difference between those reading is the time interval (duration) of that while. What "spatial changes" are you talking about?
     
  8. Oct 16, 2011 #7
    Re: My understanding of Space, Time and "spacetime"

    It doesn't really matter how one define it, as long as we agree on that it is radiation (and gravity) that defines SpaceTime. You can make it a 'whole thing' and use radiation as your proof of a 'time dilation' and Lorentz contraction, assuming a propagation. Or you can assume that SpaceTime is something defined from locality, using the same radiation as the reason why we all see it as a whole 'frame of reference', relative us observing it.

    And as Lorentz contraction indeed will redefine your 'distance' with relative motion you have a certain point there. But what about your neighbors definition? Which one is true? All of them?
     
  9. Oct 16, 2011 #8
    Re: My understanding of Space, Time and "spacetime"

    Yes, there is, and it's called time dilation and length contraction. Or do you think that when the length of, say a rod, contracts, the space it is in is unaffected? I rather think that the space in which the rod is contracts and this affects the rod that's in it.


    harrylin, if nothing changes in a closed system, can you tell whether time passes for it? Your ticking clock is a change in itself. It takes energy to tick. Time is a byproduct of energy transformation. Energy transformation is a physical process that takes place in space. If space is distorted, it will affect this process, perhaps in a such a way that, judged from another RF, the time it would take to complete this process appears different.

    See, ghwellsjr ? that's how I agree with halix :smile:
     
  10. Oct 16, 2011 #9

    DrGreg

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    Re: My understanding of Space, Time and "spacetime"

    Hmm, does that mean if I put two clocks in a box, time will pass twice as fast as a box with one clock in it?
     
  11. Oct 16, 2011 #10
    Re: My understanding of Space, Time and "spacetime"

    Of course, not. A strange question, especially coming from a PF Contributor and Science Advisor. Clocks or not, the passage of time is realized only through a change of any sort. For something to change, energy must transform. No change = no time. So, in regard to the original question, time dilation can be understood as the result of a distortion of space such that the physical process, with which time is measured (usually, an atomic clock, but it could be anything) is affected.
     
  12. Oct 16, 2011 #11
    Re: My understanding of Space, Time and "spacetime"

    Heh :)

    And if I wind the clocks counterclockwise?
    Will time go backward?

    But yeah, I've also wondered about Lorentz contractions. It's weird, like everything was some 'flat surface' able to compress with motion and gravity but only in one direction, the one you're traveling, or where gravity directs you. But maybe that is all that is needed? Could one make such an assumption, to look at what would be the minimum demand for 'shrinking a distance'?

    Simplistic again I'm afraid, but what I'm thinking of is this way Nature seems do as little as needed, and no more. As if you could put a Lorentz contraction it that category too?
    ==

    Ouch Halix, missed that reply, don't take it so seriously.
    He just wanted you to read up on it.
     
    Last edited: Oct 16, 2011
  13. Oct 17, 2011 #12
    Re: My understanding of Space, Time and "spacetime"

    Ah yes, change (physical change) is usually spatial change. However, I wonder if this is necessarily always so. Hmm... I was thinking of radioactive decay, but that also involves a spatial change. So, there may be something to it. :smile:
    Meanwhile the OP already left this thread...
     
  14. Oct 17, 2011 #13

    ghwellsjr

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    Re: My understanding of Space, Time and "spacetime"

    No, the space that contains a rod that has experienced a change in its length as a result of having been accelerated is not the slightest bit distorted or changed in any way. Light still travels through that region of space identically to the way it did before there was a rod there. We're not talking about water which is distorted by objects moving through it. There is never a measurable or detectable ether wind and there would be if what you and halix are saying were true. These ideas are not part of Special Relativity and anyone who believes them needs to have their thinking straightened out.
     
  15. Oct 17, 2011 #14
    Re: My understanding of Space, Time and "spacetime"

    I don't get it. Do you mean that time doesn't pass without a clock in the box?
     
  16. Oct 17, 2011 #15
    Re: My understanding of Space, Time and "spacetime"

    Yeah, but it would have to be a wall clock.
    Come on, are you seriously asking that?
     
  17. Oct 17, 2011 #16
    Re: My understanding of Space, Time and "spacetime"

    Ether wind, what are you talking about? Nobody has mentioned that except for you.
    Have you ever heard of mass-energy distorting light paths? General relativity has been around for almost a century but you seem not to have notice it.
    What Halix and Spacie are saying is just a non-standard terminology account of some GR concepts like gravitational time dialtion.
     
  18. Oct 17, 2011 #17
    Re: My understanding of Space, Time and "spacetime"

    yea that caught my eye too, sounds funny.

    ghwellsjr "There is never a measurable or detectable ether wind and there would be if what you and halix are saying were true."

    What's ether wind? :uhh:
     
  19. Oct 17, 2011 #18
    Re: My understanding of Space, Time and "spacetime"

    Ether wind refers to the luminiferous ether theory of 19th century that was totally surpassed by Eintein theory, but I don't think it applies to anything the OP claimed, he was talking about gravity and time dilation in somewhat naive and popular terms, nothing radical as the posts of ghwellsjr and Bill_K would have us believe.
     
  20. Oct 17, 2011 #19

    ghwellsjr

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    Re: My understanding of Space, Time and "spacetime"

    In defense of the OP, Spacie brought up ether in post #4 and said he thinks "current ether theories" "make more sense". I was disagreeing with him by saying that if a moving rod distorted his ether space, it would modify the light propagating through it in a detectable way which doesn't happen.

    There are a lot of people who don't understand Special Relativity but think they understand General Relativity and I think this is because the time dilation caused by gravity is not reciprocal and so they can accept that without any problem but they have a very difficult time understanding how two observers in relative motion can each claim that the other is experiencing time dilation. As a result, they want to find a way to make all time dilation be like it is under gravity so that the confusing aspects of Special Relativity can be explained away. That's why I tell these people that they need to learn Special Relativity first (and because it is so much easier).

    In any case, promoting false ideas about Special Relativity is not allowed on this forum and so I point it out whenever I see it. You will notice that the OP did not present himself as a learner but rather as a promoter of his personal idea. These people tend to ask for comments on their ideas in order to legitimatize their posts but it is nothing more than an attempt to entrap people who understand SR into a long drawn out process, supposedly to help the "learner", by first having to understand the nonsense they are promoting and then to pursade them of their errors, which they never accept, until the "learner" finally gets banned and the thread locked.
     
  21. Oct 17, 2011 #20
    Re: My understanding of Space, Time and "spacetime"

    Spacie brought up LET that has little to do with the ether wind you talked about, in fact LET tried to explain away any "ether wind" wich was totally discarded by the Michelson-Morley experiment.
    I won't even comment on the rest of your rant.
     
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