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On Movement

  1. Oct 15, 2008 #1
    What will happen to a body that is not moving at all? What is its time and what is the shape of its space?

    I have been wandering about these questions for a long time now. I am beginning to realize that the space time continuum of a body / object is the product of movement of that body.If the body is an element of a larger system, it will experience the space-time continuum of the larger system. If it is to exist indepenedantly, it must begin to generate its own inertial frame. The process of becoming independant is the process by which bodies and systems create their own space-time continuum. Perhaps this is how gravities are generated.
    To not to move is to either:
    a) exist in the frame of another system, or
    b) involute into oblivion and nothingness

    Can systems afford not to move at all, in the parameters of general relativity, special relativity and quantum mechanics, and still exist?
     
    Last edited: Oct 15, 2008
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  3. Oct 16, 2008 #2

    Mentz114

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    Spatial motion is relative. There is no such thing as 'not moving'. For instance I am 'not moving' because I'm sitting in a chair in a room in a building. But that means I'm only not moving relative to the earth.

    Have a look at this en.wikipedia.org/wiki/Special_relativity
     
  4. Oct 16, 2008 #3
    Mentz114 was right but I'm presuming that it's possible you could misinterpreted certain statements. Any and everything that is not being accelerated is "not moving". Two things that are "not moving" can be moving relative to each other. You have two spaceships A and B. They are both siting in space "not moving". Captain of spaceship A can still look out the window and see spaceship B zoom by at 50,000 meters per hour. Spaceship B's captain looks out and says no you went be me at 50,000 meters per hour. The laws of physics says there is nothing in reality itself that can say which spaceship is really moving and which one is "not moving". This would even remain true with or without Einstein's Relativity. The Earth gives us a reference for our common sense notion of "not moving" but it is an illusion in the grand scheme of things.
     
    Last edited: Oct 16, 2008
  5. Oct 16, 2008 #4
    I am beginning to realize that the space time continuum of a body / object is the product of movement of that body.

    Not really, space/time/mass are most likely created in unison almost simultaneously from a "big bang" or similar beginning. There can be no body without space and time....they appear more fundamental...but that's a hypothetical.

    "If the body is an element of a larger system, it will experience the space-time continuum of the larger system. If it is to exist indepenedantly, it must begin to generate its own inertial frame."

    Frames are artifical constructs we impose to explain theings....all bodies exist as parts of a larger system involved space,time,energy..

    The process of becoming independant is the process by which bodies and systems create their own space-time continuum. Perhaps this is how gravities are generated.
    To not to move is to either:
    a) exist in the frame of another system, or
    b) involute into oblivion and nothingness


    The key point is nothing is independent....it's all related....entropy, information, energy, mass,etc...it just appears different to use most likely because of spontaneous symmetry breaking early in the universe....Perhaps, to make a point I should say you have it backwards: nothing is independent of all other entities in the universe...no one element can exist independently of all others, no one is causal.

    Can systems afford not to move at all, in the parameters of general relativity, special relativity and quantum mechanics, and still exist?
    sure, buit as noted above, there is no absolute motionless velocity...it's all relative...we can only say acceleration can be detected from velocity....
     
  6. Oct 16, 2008 #5
    Lee Smolin's book, THE TROUBLE WITH PHYSICS, says that Fotini Markopoulou has showed how in loop quantum gravity quantum particles could emerge from quantum spacetime...another way to say this is that the way edges of spacetime can knot/link/kink generates elementary particles!!! So this view cleary suggests particles emerge from spacetime....our course this is theory, not experimentally verified fact.
     
  7. Oct 16, 2008 #6
    Infering from your statement that "Any and everything that is not being accelerated is "not moving" " implies that an entity with a constant velocity travelling from a point A to a point B in space is not moving. Only those accelerating are moving. Am I correct?
    What then is movement, if not a displacement of an entity to a new position from another, whether achieved by constant velocity or by constant acceleration? What is the difference in these two types of movements with respect to their outcome - say, getting from point A to point B?
     
  8. Oct 16, 2008 #7
    SO then everything must move to exist. What happens if they do not? Or what happens if a system does not move, relative to all other systems? Is this possible?
     
  9. Oct 16, 2008 #8

    russ_watters

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    I'm not sure I like the way my_wan worded that sentence, though the expansion is fine. I would say that "any and everything that is not being accelerated can be considered not moving". Meaning you can choose if you consider yourself to be stationary and another object moving or that object stationary and you moving (if the displacement between you is changing).

    This is called the principle of relativity and just to be clear, it's been a fundamental principle of physics since Galileo started to turn physics into a science.
    I don't know where you got that idea. Nothing anyone said implies it.
    Sure, it's possible: I'm sitting on my couch right now and I declare myself to be stationary and all other objects with a displacement changing relative to me to be moving!
     
  10. Oct 16, 2008 #9

    Doc Al

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    You are using a rather unusual meaning of "not moving", to say the least.

    I recommend sticking with what Mentz114 said. "Not moving" is meaningless unless you specify with respect to what.
     
  11. Oct 16, 2008 #10

    atyy

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    Constant velocity and variable velocity are both motion. The difference in the constant velocity case is that if I am stuck in a small room with no windows, I cannot determine whether I am stationary or moving with respect to an "outside object", which seems obvious since velocity has to be defined relative to an "outside" or "outside object". What is surprising to me is that I can detect an "outside" or "outside object" without a window if I happen to measure a non-zero acceleration. In that case, I am either accelerating relative to the "outside" or I am "stationary" (or at least not free falling) in the gravitational field of an "outside object". If I carry an electric charge and see whether it gives off radiation, I can do even more (but that is perhaps already a non-local experiment).
     
  12. Oct 16, 2008 #11
    But you are still moving, nonetheless. You are riding on the inertial frame of this earth. And as long as the earth is moving, you are also moving. It is impossible to just declare yourself stationary.
     
  13. Oct 16, 2008 #12
    How is it possible to "detect an "outside" or "outside object" without a window if I happen to measure a non-zero acceleration"? How does acceleration affect electric charges?
     
  14. Oct 16, 2008 #13

    Consider two bodies A and B in space. Consider them approaching each other. How can you prove or disprove that A is moving towards B or vice versa or both moving towards each other. In space, I find this phenomenon quite paradoxical because, without reference to a third entity, it can be concluded and quite correctly, that if A is moving towards B, then B is also moving towards A in the same rate as A is moving towards B, irrespective of which body expends the energy to achieve the result. A body that moves toward another body is the same as the other moving towards it. If the other is not moving, then it is nonexistent. How can it exist in space and not move?
     
  15. Oct 16, 2008 #14

    russ_watters

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    No, it really isn't. As Doc said, motion is something that you measure between yourself and something else. And even if there is a change in displacement between you and something else, either object can be considered the stationary one (if the rate is constant).
    You can't! That's the entire point of what we are telling you here. Either one can be considered 'the stationary one'.
    No. If one of them is expending energy, you mean it is accelerating. That makes the situation no longer symmetrical and makes that one 'the moving one' (assuming they started out stationary wrt each other).
    I'm sitting on my couch, not moving, and I exist. I don't know why you would think otherwise. Speed is a number and zero is just another number. There is no reason that if an object is moving at 0 m/s, 1 m/s, or 10000 m/s you should apply a concept of "exists" or "doesn't exist" to an object who'se speed has a value of one of those numbers. Speed has nothing to do with "exists".
     
    Last edited: Oct 16, 2008
  16. Oct 16, 2008 #15
    You exist because you are moving, even when you are sitiing on your couch. Your movement is determined by the inertial frame of the earth. You are not yet independant enough to claim that you exist without this inertial frame. Not at this point. Until you exert some kind of energy to create your own inertial frame, you cannot compare yourself with / to other systems, but that of earth and other systems
     
  17. Oct 16, 2008 #16

    russ_watters

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    Sorry, but that statement has no physics in it. It makes no sense: It's 'not even wrong'.
    Sorry, that just plain isn't the way it works. This is how it works:

    My speed is 1,000 mph.
    My speed is 0 mph.

    Both of these statements are equally true.
     
  18. Oct 16, 2008 #17
    I infer that symetric movements refer to motions with constant velocities and non-symetric movements refer to motions with one or the other system moving at a constant acceleration. What do we infer for a system with two bodies moving towards themselves at constant but different velocities? Are they symetric or non-symetric?
     
  19. Oct 16, 2008 #18

    russ_watters

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    Close - both can be accelerating and that could make the situation non-symmetric.
    Two objects moving toward each other have only one speed wrt each other, so the question is meaningless. Or, rather, they are symmetric because there is only one speed.
     
  20. Oct 16, 2008 #19
    What if the earth stops to move, as we know. What happens to our existence and our speed and that of earth and all matter comprising earth?
     
  21. Oct 16, 2008 #20

    russ_watters

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    If a T-Rex tears open my living room and eats me, I'll cease to exist. That has nothing to do with physics either.
     
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