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The twins scenario illustrates time differential, which is an objective (frame independent) fact. Time dilation is a coordinate effect and is entirely frame dependent. Just pointing this part out so hopefully the terms get used more correctly.
Quote from: hamdani yusuf on 16/06/2023 15:24:09So he sees the giant clocks tick faster than his onboard clock, both on going and return trips.It only appears to run fast if it is approaching you, which is true only half the time. I didn't offer an explanation. You asked what the rocket guy would see on the clocks as they passed by, and I answered that.More details: Suppose he always watches the Earth clock. For 65 days it is receding and during those 2+ months it appears to advance about 4 minutes, 22500x slower. On the 2nd leg, Earth is approaching and it appears to run about 45 times faster, so it appears to gain about 8 years in those 65 days.The Earth observer sees the same thing if he watches the ship clock. 22500x slower when outbound and 45x faster when it is returning, but in his case, the vast majority of the time (over 8 years) is spent watching it recede, and the return leg appears to take only a day and a half.
So he sees the giant clocks tick faster than his onboard clock, both on going and return trips.
But that's not what the explanation shown by MinutePhysics' video.
Let me rephrase my statement you quoted. His onboarding clock ticks slower on average than the giant clocks.
Traveling twin sees the giant clock the he is passing by showing the time according to Origin's calculation. Earth clock ~ 4Second clock ~ 5Third clock ~ 6Fourth clock ~ 7Star clock ~ 8, then return. Fourth clock ~ 9Third clock ~ 10Second clock ~ 11Earth clock ~ 12
Which clock ticks faster is a frame dependent thing, and no frame was specified, so no, this isn't correct.
For instance, from the ship PoV, at the start, the 2nd clock appears to read 3 (just like you said in post 36). 16.3 days later when the 2nd clock passes by, it reads 5, which means it appears to run ~45x as fast because it is approaching, exactly the rate that I posted.
Imagine we have CCTV in every giant clock.
Quote from: hamdani yusuf on 17/06/2023 12:20:45Imagine we have CCTV in every giant clock.Why? What would be the point?
So we can get the observations from both frames of reference locally, where the events take place, ie, when the spaceship is passing a giant clock.
The CCTV s allow the earth twin to trace the events locally in his own frame of reference, and compare the reading of spaceship clock and giant clocks as they are passing by.
Quote from: hamdani yusuf on 17/06/2023 15:59:19The CCTV s allow the earth twin to trace the events locally in his own frame of reference, and compare the reading of spaceship clock and giant clocks as they are passing by.I don't see how that would be possible. If the transmitter of the CCTV is 2 ly away the person on earth won't receive the transmission for 2 years, so what's the point?
The CCTV can be replaced by independent observers which will communicate the results.
Quote from: hamdani yusuf on 17/06/2023 23:27:00The CCTV can be replaced by independent observers which will communicate the results.I see, there is no point to having a CCTV. Actually there is no point in running this impossible experiment anyway since we already know what the results will be.
Quote from: Origin on 17/06/2023 17:06:00Quote from: hamdani yusuf on 17/06/2023 15:59:19The CCTV s allow the earth twin to trace the events locally in his own frame of reference, and compare the reading of spaceship clock and giant clocks as they are passing by.I don't see how that would be possible. If the transmitter of the CCTV is 2 ly away the person on earth won't receive the transmission for 2 years, so what's the point?The point is to capture the events locally, which will be investigated later on. They're for matching up between traveling clock and giant clock as they are passing by. That becomes necessary since the video mentions that the clock reading can be affected by observer's motion and position when done remotely. The CCTV can be replaced by independent observers which will communicate the results. When the information arrive isn't important, but what they tell is what's important.
The observation of the accelerated twin is equally valid. It is just that his observations are effected by his acceleration while he is actively accelerating. This includes clocks in the direction of the acceleration running fast compared to his own by a factor determined by the magnitude of the acceleration and the distance to the clock.
Thought experiments are only useful to examine consistency among many assumptions taken to build a model. It can't check if the model accurately represent physical reality. That would take physical experiments.
We've agreed what the giant clocks show when the traveling twin is passing them. What would the traveling clock show in each event, when observed at the same time and position?
The importance of local observers is made clear by Janus' post that's also pointed out by Halc.
Quote from: hamdani yusuf on 17/06/2023 01:02:06Let me rephrase my statement you quoted. His onboarding clock ticks slower on average than the giant clocks.Which clock ticks faster is a frame dependent thing, and no frame was specified, so no, this isn't correct.Relative to Earth, the ship clock ticks slower. Relative to some inertial frame in which the ship is stationary, the Earth clock and all the giant clocks tick slower. QuoteTraveling twin sees the giant clock the he is passing by showing the time according to Origin's calculation. Earth clock ~ 4Second clock ~ 5Third clock ~ 6Fourth clock ~ 7Star clock ~ 8, then return. Fourth clock ~ 9Third clock ~ 10Second clock ~ 11Earth clock ~ 12Yes. This is consistent with the numbers in my prior post.For instance, from the ship PoV, at the start, the 2nd clock appears to read 3 (just like you said in post 36). 16.3 days later when the 2nd clock passes by, it reads 5, which means it appears to run ~45x as fast because it is approaching, exactly the rate that I posted.
Quote from: hamdani yusuf on 18/06/2023 03:01:49We've agreed what the giant clocks show when the traveling twin is passing them. What would the traveling clock show in each event, when observed at the same time and position?Halc has given you those numbers twice.Quote from: hamdani yusuf on 18/06/2023 03:22:44The importance of local observers is made clear by Janus' post that's also pointed out by Halc.Nobody has said otherwise. Your idea about the CCTV is an unnecessary complication, you should just drop it.
The CCTV are necessary to pinpoint where and when the asymmetry appears. Minutephysics video seems to conclude that it appears at the turning point, when the spaceship reverses its direction.
The asymmetry was known once the itinerary was made. Everybody from anywhere can see it. I have no idea why you think a CCTV present at the star-clock would show anything not already visible to everybody else, including the ship which happens to actually be there.