Thinking about the physics of time (again)

Discussion in 'Bad Dog Cafe' started by TheGoodTexan, Nov 5, 2020.

  1. 61fury

    61fury Friend of Leo's

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    Duplicate post.
     
  2. 24 track

    24 track Doctor of Teleocity Ad Free Member

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    I havent read all the replies (my bad) but experiments with 2 matching clocks were done with both clocks sync'd one was launched on the shuttle the other was earth bound ,when the clock was returned to earth there was a notable how ever minute difference in the readings , I do believe the series "how the universe works" did a similar experiment with one clock at sea level and the adjacent clock at the top of a New York sky scaper and for what ever the sample period was , there was a difference recoded as well . to demonstrate Einstien's theory .
     
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  3. Masmus

    Masmus Tele-Holic

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    If there are two spaceships and one stays stationary while the other goes in a circle and returns from an observer on both ships it would appear that the other is moving, however if the one going in a circle is traveling at 30 meters/sec or any speed that appears constant it is in fact accelerating.
     
  4. teleblastard6

    teleblastard6 TDPRI Member

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    For me, time is the most confusing & mysterious aspect of physics
     
  5. Obsessed

    Obsessed Telefied Silver Supporter

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    Even though I loved advanced math and advanced physics in college, we occaisionally need to step back and away from technology to gain perspective. Our "time" is based upon one rotation of the Earth and has been long before Archimedes. How we divided up a "day" is arbitrary. True that we are only experiencing a sunrise and sunset, however, we nevertheless experience one rotation of the Earth. Plus one rotation of the sun for our Earth "year" too.

    Just sayin'. Carry on.
     
  6. TeleTucson

    TeleTucson Friend of Leo's

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    Based on your later post, it seems that you know the answer. :) It is not symmetrical.

    One accelerated, deaccelerated to turn around, accelerated again, and deaccelerated to compare clocks. To calculate the dilation you can make the unrealistic assumption that the acceleration/deacceleration segments are instantaneous and don't rip your body apart and you'll get the right answer. But one system remained in a constant inertial frame and the other did not.

    If each accelerated/deaccelerated in opposite directions and went half of the relative speed and came back, their clocks would read the same, because that would indeed be symmetrical.
     
  7. trev333

    trev333 Telefied Ad Free Member

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    "Time may change me
    But I can't trace time"...:D
     
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  8. Brendo

    Brendo Tele-Holic

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    I haven't read every post.

    But... If the clock on earth, and the clock on the shuttle showed different times on their return together....

    Is this a change in how the clock measures the time (as in the units of time measured alter slightly) or the actual quantity of time itself is different?

    Better way to paint the picture. Two ten litre buckets full of water. The earth bucket uses the same cup to empty it, but the shuttle bucket uses cups of slightly different sizes as it moves away and back. Both will be empty, both will have had the same quantity of waater removed from them, but they will measure a different amount of cups of water removed.

    ?
     
  9. 24 track

    24 track Doctor of Teleocity Ad Free Member

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    we can travel forward through time we cannot travel back through time, I realized that we (well most of us) own time machines .
    EG : I get up one morning and go to work,
    lets say my work is exactly 100 miles away , I'm driving at exactly 100 miles per hour so ( for the sake of discussion ) I arrive at my destination in exacly 1 hour , I have traveled through time 1 hour and have arrived at my destination 100 miles away, hence I have travell through time (albeit forward) to get to new destination.
     
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  10. TeleTucson

    TeleTucson Friend of Leo's

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    Yours is an unnecessarily energy-expending time machine. I can lay in bed having a nice dream and move forward in time without breaking a sweat! :)
     
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  11. Obsessed

    Obsessed Telefied Silver Supporter

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  12. 24 track

    24 track Doctor of Teleocity Ad Free Member

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    but you have traveled through time , you've passed stationary through time , a totally different machine , ( I read that once on a cereal box!) :lol::lol::lol:
     
  13. JL_LI

    JL_LI Poster Extraordinaire

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    I think about time in three frames of reference. I think about what @Obsessed describes as “local” time, the time of clocks and calendars. One aspect of relativistic time, or space time is tied to the curvature of space caused by massive objects. Another aspect of relativistic time is time dilation at relativistic velocities. The third frame of reference is the flow of time. I see this as a result of quantum mechanics. In the quantum universe, all possible outcomes are valid until the collapse of the wave function. The particle is detected or it interacts in some permitted way with another particle. That event has a probability of less than 1 because there are many ways the event can unfold. Reversing the event is possible, but with a lower probability than the event just detected or measured. The probability of reversing all events is too small to conceive of even if we know how they could be reversed. This makes time irreversible on the macro scale. A single event, possible no matter how improbable. Time, space time, the flow of time? We experience all of them even if what I refer to as local time is all we are aware of. I experienced local time acutely this morning when an idiot who was late for work cut me off. My GPS continued to work so I guess I experienced relativistic time as well, even though I wasn’t aware of it. Quantum mechanics determines the repetition frequency of my pulsed laser. It’s all real and all part of my daily experience.
     
    Last edited: Nov 5, 2020
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  14. uriah1

    uriah1 Telefied Gold Supporter

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    I remember as a kid finding a train graphic explaining special relativity and time dilation Can’t find that one 989F63CD-3531-4774-A4EA-29EF7C4695F8.jpeg
     
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  15. BigDaddyLH

    BigDaddyLH Tele Axpert Ad Free Member

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    I get it now! If my spaceship is traveling with constant velocity, it might as well be standing still -- that's the relativity of the frame. But if my spaceship is accelerating (and, yes, traveling in a circle is accelerating) I can feel that in the spaceship -- it might be pinning me in my seat! That's what's different. Thanks!
     
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  16. SRHmusic

    SRHmusic Tele-Afflicted

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    My assumption is it's because car manufacturers are too cheap to give you a high accuracy clock, and the ones they use are toleranced to always run at least a little fast. (You would not want a slow running clock.)
     
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  17. teletimetx

    teletimetx Doctor of Teleocity

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  18. Masmus

    Masmus Tele-Holic

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    Some have theorized that antimatter such as a positron is just its counterpart moving backward in time.
     
  19. Greggorios

    Greggorios Friend of Leo's Gold Supporter

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  20. Obsessed

    Obsessed Telefied Silver Supporter

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    Yes. Excellent. "Time" is relative to what frame of reference that we are discussing. My favorite time reference is the light arriving to Earth from some far away object in the Universe and knowing that the actual "light" that has arrived was emitted from that body very, very long ago. We talk about the speed of light traveling in MPH, but when we discuss light coming from a star, we talk about it in distances that refers to light traveling distance per year as a unit of measurement.
     
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