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Can somebody reexplain me Newton ?

  1. Mar 31, 2005 #1
    Since relativity, we know time is attached locally to an observer....
    But at Newton's time was in some sense global...(the same for every particle you describe).

    So what does that global time meant ( when compared to the meaning it has in the relativistic framework) ?

    It seems to me it's now inimaginable..some kind of universal clock...but this has no sense any more..(Like if the observer had two kind of time : a local and a kind of global one ???)

    Does somebody sees the same problem as me ?
  2. jcsd
  3. Mar 31, 2005 #2
    We now know that Newton's physics is just a good approximation that happens to work extremely well for our immediate human environment. Don't forget that it is such a good model that it took the scientific community over 200 years to come up with anything better.

    Even so, you are right. Nobody can turn the clock back on relativity :wink:
  4. Mar 31, 2005 #3
    I mean since Bell's inequality is violated we could imagine that all the particles were correlated at BigBang time, so that there could exist a clock in every particle that is correlated to all the others, giving a global time (since when one of these clocks ticks, then all the others, instantaneously [globally], tick too)...?? (I don't know if entanglement remains conservated during particles interactions)
  5. Mar 31, 2005 #4


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    Your idea sounds more like Leibniz's monads than anything of Newton. The monads were self-sufficient, so they had their own times and all, and relationships between monads were what makes things happen.
  6. Apr 16, 2005 #5
    I think time is a social construct. In reality everything is driven by energy & work (including our brain and muscles). I'm not sure about spacetime though. Some people even reject the physical existence of space in which mass-energy moves. I believe they are correct.

    The EPR paradox is a good example.

    And today do we really understand gravity, energy, work, power, friction, heat, radiation, magnetism, superconductivity, nuclear fusion in planets cores etc? I highly doubt it.
    Last edited: Apr 16, 2005
  7. Apr 17, 2005 #6
    Well, I don't think we have to reject those teaching about space-time...the problem is just to find a way to reconciliate both view (in my opinion). And in some sense you need space-time to define energy and vice-versa (following general relativity)
  8. Apr 17, 2005 #7
    I believe that space, time and dimensions are abstract quantities but they are not physical. We don't need space and time to explain the universe because everything is driven by energy and work.
    Last edited: Apr 17, 2005
  9. Apr 17, 2005 #8


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    Are momentum and angular momentum not physical quantities ? If you chuck a large blob of putty at a block, will you not move the block ? And how do you talk of things like momentum without using quantities like sapce and time ?

    Isn't it a physical reality that you can reach out and touch your monitor faster than you can reach proxima centauri ?

    Believe it; space and time are at least as physical as work and energy.

    Now where's that thread where everyone was saying that energy is merely an abstraction ?
  10. Apr 17, 2005 #9
    No doubt. Momentum, angular momentum, spin and mass-energy are all physical but time i don't think so. Do we have any physical evidence for the existence of time? What about space? What is space without mass-energy?

    The dilemma i recognize is that general relativity puts a lot of emphasis on space-time but fails to define the concepts properly. On the other hand, chemistry, quantum mechanics, nuclear physics, plasma physics and particle physics put much less emphasis on concepts such as space & time. For example in electricity, we don't say that an electric charge warps spacetime.

    So what is the difference between the theories? Why do we need two theories to explain mother nature?

    Is energy and work not enough to explain them?

    So space = distance but distance is also abstract because it depends how we measure it.

    What is space-time if not mass-energy and work?

    I see space-time as an abstract entity. It's like a set with some additional structure which we put on it.
    Last edited: Apr 17, 2005
  11. Apr 17, 2005 #10


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    How you see things is your choice.

    However, the discussion here is not about how you see space-time.
  12. Apr 18, 2005 #11
    I don't "see" spacetime. I believe it does not exist. The problem is understanding gravity at the quantum level. Like we don't say that a proton curves spacetime, there is no reason to believe that the sun and planets do so.

    Everything in nature has an energy/power source. Nothing works on spacetime. That's why everything is in such a beautiful equilibrium with no scary singularities.
    Last edited: Apr 18, 2005
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