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I Musings, seeking opinions about the nature of time

  1. Sep 5, 2018 #1

    Sorry, I had to pick a prefix but please feel free to reply as you see fit. I just joined to seek opinions on various things and hopefully learn some other things as well. I am a retired GIS analyst programmer. Completed 1st level multistrand science and maths in high school 1976 but didn't pursue that kind of science career. I have done some self-study in various areas over the years though. Anyway, I just wanted run a few things past more knowledgable people for your opinions.

    This may be a bit esoteric and weird. I was wondering, what is time exactly? So, far it seems no one has any real idea though we measure change as an indicator of time, we don’t measure time directly. Is that right? Also, it seems a mystery that time runs only forward and seem to run at a constant rate. Then I figured that we only perceive time in relation to memory. We have past memory and as we experience the present, create new memories. But what if time ran backwards, our future memories would be erased as we returned to past temporal memory states. So, at any point in time, we would only have past memories up to the present. That is, our perception would be the same as when time moves forward. Does this make sense? Would this not mean that we can only ever perceive time going forward whichever way or speed it ran? What if time ran at varying speeds, would not all physical function, memory, rotations, orbits, C and radioactive decay change speed to match time?

    Therefore, it seems to me that while we are in the space time stream, we have no idea what is actually going on in an absolute sense. Is the universe collapsing as time runs back for example? How could we possibly know?

    I suppose I am thinking in terms of whatever was before the big bang as a term of reference, was there even space time then? I guess nobody knows for sure but what do you suspect, could space time be generated out of that event and expanding with the energy field? That’s probably more than enough really big questions, especially that last one.


  2. jcsd
  3. Sep 5, 2018 #2


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    Staff: Mentor

    It is very difficult to improve on Einstein's answer: Time is what a clock measures.

    It's worth googling for this phrase (but be careful - google will serve up generous amounts of drivel along with the good stuff) to get an understanding of what Einstein meant and how it works with the mathematical (that is, the only unambiguous and complete) treatment of time in modern physics. It is also somewhat futile to take on the questions that you're asking here without that understanding.

    Because of that futility this thread is closed. However, threads with more tightly focused questions based on modern physics will be welcome.
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