• btaf45@lemmy.worldOP
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    1 year ago

    “We should use Earth’s time, which happens to be the universal time,

    Earth time is not universal time. Maximum time is universal time. No local reference frame can achieve maximum time.

    Zebulon 5 clocks are the ones that tick the fastest

    They won’t be ticking at maximum time either. No local reference frame can achieve maximum time.

    how would you resolve this dispute? Whose clock is actually faster?

    Neither clock is as fast as the maximum time flow. Planet Earth calculates it’s percent of the maximum. Planet Zebu also calculate their percent of the maximum. To convert you could go from Earth time to maximum time to Zebu time, although I suspect they would already be very close in their percentages. For this purpose you can ignore speed and calculate time dilation using gravitational time dilation + acceleration time dilation. Neither planet is going to be accelerating towards the other. Time dilation due to non-accelerating motion is more optics than real time dilation, because maximum time does not require you to wait for light from another source to travel towards you.

    • TauZero
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      1 year ago

      Time dilation due to non-accelerating motion is more optics than real time dilation

      I’m afraid it’s both… Just to be clear, you are aware that relativistic time dilation is very much real, right? There is the doppler component AND the relativistic component, the latter of which you can’t get rid of regardless of the correction for perspective. That was the whole weird part with the special relativity, want to be sure we agree here.

      For this purpose you can ignore speed and calculate time dilation using gravitational time dilation

      Hold on, let’s not ignore the speed! I agree that for gravitational time dilation there is a time rate that is the maximum rate possible, which is as far away from any massive bodies as possible - away from planets, away from stars, even away from galaxies, and certainly away from any supermassive black holes. But you haven’t been talking about gravitational time dilation all this time, have you? I was about to suggest doing the opposite: for this purpose let’s ignore the mass of Earth and Zebulon for now as that is negligible, and just focus on the speed, which is very much not! Zebulonians are saying that for every hour on Zebulon 5, only 59 minutes 42 seconds pass on earth! (3600 * (1-0.1**2)**.5) This is way more than some microseconds per year that you accumulate from being in the Earth’s gravity well.

      acceleration time dilation

      What’s that?

      • btaf45@lemmy.worldOP
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        1 year ago

        you are aware that relativistic time dilation is very much real, right?

        I do not agree that 2 objects can both have time flow rates faster or slower than the other. That is impossible, so it is really optics. If 2 objects each think the other is moving towards them at a faster or slower time flow rate, you can ignore that. Because neither has a time flow rate faster than the other even if they both think they do. What matters is (1) time dilation due to acceleration and (2) gravitational time dilation. We do not age faster/slower just because another planet exists. And they would not age faster/slower just because we exist.

        Look at this article below. Your scenario is #1 (2 objects moving past each other) Author says that time APPEARS to pass more slower for the other object. My scenario is #2 (gravitational time dilation). It says your head AGES FASTER than your feet.

        https://bigthink.com/starts-with-a-bang/time-run-slow-early-universe/

        [Time dilation has now been shown to apply in three separate instances. (1). When two objects pass each other at high speeds, each one sees the other as having their clocks dilated, and time appears to pass more slowly for the other, even though each experiences time as normal. (2). When two objects are in different gravitational fields, the one that’s deeper in a gravitational field experiences time passing more slowly than the one in a shallower field, and as a result, your head ages faster than your feet when you stand on Earth. (3). And cosmologically, when a local observer sees a signal emitted from an object across the distant Universe, the expansion of the Universe will both stretch the wavelength of that signal and also stretch it out, in time, when we observe it.]

        For purposes of determining what your time dilation is as a percent of the maximum, you never need to directly compare 2 reference frames and “observe events” or observe light traveling over long distances from another object. You ignore the other planet and compute your percent of the maximum by adding your gravitational time dilation with your time dilation due to acceleration. The other planet does the same. Since neither planet accelerates, it comes down to how big the planets are and the gravitational time dilation that they generate. Since this affect is very small, both planets time flow rates will be very close to the maximum. Let’s say that Earth’s percent is 99.999% of the maximum. Zebu is a bigger planet, so their time flow rate is only 99.998% of the maximum. You simply sync the time by computation. On earth, you add 1 second to every 99,999 seconds to track the maximum. If you then want to go to Zebu’s time flow rate from the maximum, you would then subtract 2 seconds for every 100,000 “maximum time” seconds.

        ! I agree that for gravitational time dilation there is a time rate that is the maximum rate possible, which is as far away from any massive bodies as possible - away from planets, away from stars, even away from galaxies, and certainly away from any supermassive black holes.

        Actually this is not the case. Even a single atom would generate its own gravity field. That is why no matter can ever obtain the “maximum” time flow rate.

        Zebulonians are saying that for every hour on Zebulon 5, only 59 minutes 42 seconds pass on earth!

        That is because they are observing our light moving over large distances, which they don’t need to do. They don’t need to observe us to know what their own time dilation is. They do not age faster or slower just because we exist. And we do not age faster or slower just because they exist. They should be ignoring our planet completely and computing their own time dilation as a percent of the maximum, based on gravitational time dilation.

        • TauZero
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          1 year ago

          I do not agree that 2 objects can both have time flow rates faster or slower than the other. That is impossible, so it is really optics.

          Great! I’m glad we found your core mistaken belief and this conversation has been productive! The 2 objects do indeed each have time flow rates faster than the other. As to how that impossible paradox is resolved they teach that in a special relativity class or textbook. If you don’t believe me you could post in ask science with “Is special relativity time dilation real or just optics?” and others will confirm.

          • btaf45@lemmy.worldOP
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            1 year ago

            The 2 objects do indeed each have time flow rates faster than the other.

            They only have the perspective of having a faster time flow rate. If both objects were magically transported together thru a wormhole, their clocks would show the same elapsed time. It would be logically impossible for each clock to be ahead of the other clock. The analogy that explains this is that if 2 people walk away from each other, they both look smaller to each other. But we know that is just optics. They are really the same size as always.

            You are talking about symetrical time dilation. Symetrical time dilation does not cause differential aging. I am talking about the 2 types of time dilation, both non symetrical, that cause differential aging. Those 2 types of time dilation are (1) gravitational time dilation, and (2) time dilation due to acceleration (which resolves the twin paradox). Symetrical time dilation can be completely ignored in calculating your time flow rate as a percent of the maximum, because it does not cause differential aging. Symetrical time dilation is simply a way to track a difference in perspectives.

            If you don’t believe me you could post in ask science with “Is special relativity time dilation real or just optics?” and others will confirm.

            Yes symetrical time dilation is “real” in the sense that it has been defined to be one of the various types of time dilation. But the symetrical time dilation that you are talking about does not cause differential aging as does time dilation caused by acceleration and gravity fields. It is well known that symetrical time dilation does not cause differential aging. It is actually impossible for symetrical time dilation to cause differential aging, because then it wouldn’t be symetrical.

            https://physics.stackexchange.com/questions/53009/is-time-dilation-an-illusion#:~:text=It has been confirmed by,that time dilation is real.

            [Gravitational or else called acceleration time dilation, has actual effects on clocks since it slows down matter vibrations and thus time evolution of matter and therefore tick rates on clocks…Kinematic time dilation or else named constant velocity time dilation is a different phenomenon. It is an apparent time dilation effect]