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I A few questions about Time

  1. Dec 5, 2016 #1
    1. Can we imagine time as the fourth dimension? If so why is this dimension different from other 3 spacial dimension in the way that we cant move forward and backward as we want, we are ever bound to have a velocity through this dimension and can't stop with respect to someone else's motion through time.

    2. Is the concept of time necessary for physics? Do time have an independent existence? Can we refer to time without motion? If no Matter exist in the universe or no Matter moves relative to any other Matter, wont Time be meaning less?

    That's all for now. I'll try to add questions later. If anybody finds more valid questions that would boost this discussion, they can post it. Invitation are send to all curious minds !
  2. jcsd
  3. Dec 5, 2016 #2


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    We already have time incorporated as a "4th dimension", as in Special/General Relativity.

    A "dimension" in this case need not strictly be a spatial dimension. There's nothing here that says that the word "dimension" has to be tried to space. It can be a "coordinate system" or a phase space that is required to fully describe something.

    Do you think space is necessary and can exist without time? The constant speed of light "c" has both spatial and temporal parts. In Relativity, it is this constant that connects space and time. As a fundamental physical constant, do you think this constant will exist without time?

    A matter sitting still in space (assuming in reference to some coordinate system) STILL undergoes change in time. It doesn't undergo a change in spatial coordinates, but it certainly undergoes a change in time!

    There have been numerous threads on this topic already. You might want to spend time searching and browsing those threads. Also note that many of them did not meet a peaceful ending.

  4. Dec 5, 2016 #3


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    Yes. There's are well-developed methods for treating time as dimension, and nothing in modern technology would work if those methods were invalid.

    Judging by your other questions, you have maybe a century or so of catching up to do before you can talk sensibly about how time is handled in modern physics. A good starting point might be Taylor and Wheeler's book "Spacetime physics"; it will also help answer your next few questions:
    The language of physics is math, and the concept of time is essential to that math. Until you've learned and are using the math, there's no way of taking on these questions.
  5. Dec 5, 2016 #4


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    This thread is closed.
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