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This is wrong, and the video is wrong if it says this. GR says the two are equivalent only locally, not over any significant distance. The two are very distinguishable over distance.The problem with using videos for education is so many of the videos have no peer review.
I've never had the time to search for good ones, and I've never chosen any to do the actual learning.Watch out for any video that claims to be the one correct way to explain the situation.
It seems like the confusion is more common than what we think.
There are good videos out there, but hunting down bad ones seems a favored pasttime to those that don't want to learn. Take the advice of other posters and find a good physics text if you actually want to learn this, which I suspect you don't. Stay away from you-tube, pop sites, and especially social media.
Quote from: hamdani yusuf on 30/09/2023 10:49:38It seems like the confusion is more common than what we think.Just in the popsci world. As I said before if you want to learn the physics relativity go to a university site that has open courseware and do the course.
nor did you ask it about 'the cause' of the differential aging.
The twins age differently because of a phenomenon called time dilation. Time dilation is a consequence of special relativity, which is a theory of physics that describes how space and time are interwoven and how they are affected by the motion of objects.According to special relativity, time passes more slowly for objects that are moving at high speeds. This is because the faster an object moves, the more its length is contracted and the more its time is dilated.In the twin paradox, the traveling twin is moving at a high speed relative to the stay-at-home twin. This means that the traveling twin's time will pass more slowly than the stay-at-home twin's time. As a result, when the traveling twin returns to Earth, they will have aged less than the stay-at-home twin.
If it doesn't say that each of them sees the other twin age faster when approaching, then the video is wrong.
From the traveling twin's frame of reference, the Earth twin appears to be accelerating during the turnaround phase of the journey. This is because the Earth twin is moving relative to the traveling twin, and the traveling twin sees the Earth twin as changing its direction of motion.Acceleration breaks the symmetry of the situation. The traveling twin does not accelerate during the turnaround phase, while the Earth twin does. This asymmetry is what allows for the difference in aging.Another way to think about it is that the Earth twin's worldline is not a straight line in spacetime, but rather a curved line. The traveling twin's worldline, on the other hand, is a straight line. This difference in worldlines is what accounts for the difference in aging.The traveling twin can use this asymmetry to explain why the Earth twin has aged more. They can argue that the Earth twin's acceleration has caused their time to run faster.This explanation is consistent with special relativity. Special relativity allows for different observers to measure different amounts of time for the same event, depending on their relative motion.It is important to note that the traveling twin's explanation is not the only possible explanation for the difference in aging. The Earth twin can also give an explanation from their own frame of reference. They can argue that the traveling twin's time has run slower because they have been moving at a high speed.Both explanations are valid, and they are both consistent with special relativity. The key to understanding the twin paradox is to realize that the twins' situations are not symmetrical. The traveling twin undergoes acceleration during the turnaround phase of the journey, while the stay-at-home twin does not. This asymmetry is what allows for the difference in aging.
From the Earth twin's frame of reference, the traveling twin is moving at a high speed relative to them. According to special relativity, time passes more slowly for objects that are moving at high speeds. This is called time dilation.Therefore, the Earth twin will observe that the traveling twin has aged less than them when they return to Earth. This is because the traveling twin's time has been dilated due to their high speed of motion.The amount of time dilation that occurs depends on the speed of the object and the distance that it travels. For example, if the traveling twin travels at half the speed of light for 10 years, they will have aged only 5 years when they return to Earth.Why does the traveling twin not experience time dilation from their own frame of reference?This is a common question, and the answer is that the traveling twin does not experience time dilation from their own frame of reference because they are not accelerating. Acceleration breaks the symmetry of the situation, and it is what allows for the difference in aging between the twins.The traveling twin is moving at a constant speed for the majority of their journey. It is only during the turnaround phase of the journey that they accelerate. However, this acceleration is enough to break the symmetry and cause the traveling twin to age less than the Earth twin.How to explain this to the traveling twin?The Earth twin can explain to the traveling twin that their time has been dilated due to their high speed of motion. They can also explain that the traveling twin does not experience time dilation from their own frame of reference because they are not accelerating.The traveling twin may find this explanation difficult to believe, because they will feel like they have experienced the same amount of time as the Earth twin. However, this is due to the effects of special relativity.The traveling twin can verify the Earth twin's explanation by comparing their clocks to the clocks on Earth. They will find that their clocks have fallen behind the clocks on Earth. This is due to the time dilation effect.The twin paradox is a challenging concept to understand, but it is an important one in special relativity. It demonstrates that time is not absolute, but rather relative to the observer's frame of reference.
To the best of my knowledge, the Michelson-Morley experiment has not been replicated on the International Space Station (ISS). This is likely because the experiment is quite complex and requires a very stable platform to be successful. The ISS is in a microgravity environment, which can make it difficult to achieve the stability required for the experiment.However, there have been other experiments conducted on the ISS that have tested the Michelson-Morley hypothesis. For example, in 2009, scientists conducted an experiment using optical resonators that confirmed the absence of any aether wind at the 10−17 level.The Michelson-Morley experiment was a landmark experiment that helped to pave the way for Einstein's theory of special relativity. The experiment showed that the speed of light is the same for all observers, regardless of their motion. This result was unexpected at the time, and it led to a fundamental shift in our understanding of space and time.Despite the fact that the Michelson-Morley experiment has not been replicated on the ISS, the results of the experiment have been replicated many times on Earth. These results have been confirmed with ever-increasing precision, and they provide strong evidence for the validity of special relativity.
There is one STR, and it is mathematically perfect, meaning it cannot be falsified from an armchair, only by empirical means. If somebody actaully alters the theory, that person is wrong, but most just convey the concepts in different ways. I've seen no wrong replies to you for instance. You're the only one making blatantly incorrect assertions.
I asked Bard, has Michelson-Morley experiment been replicated in ISS?
The video from MIT Opencourseware doesn't say that.
Quote from: hamdani yusuf on 02/10/2023 13:52:40I asked Bard, has Michelson-Morley experiment been replicated in ISS?If you ask a chat bot a question, it will chat with you, what it chats about may or may not be true, it's just chatting.
Quote from: hamdani yusuf on 02/10/2023 13:30:16The video from MIT Opencourseware doesn't say that.I guess the lecture wasn't discussing the doppler effect then, was it.
The lecture was discussing twin paradox. The lecturer didn't think that doppler effect was necessary to explain it.
Quote from: hamdani yusuf on 06/10/2023 04:27:02The lecture was discussing twin paradox. The lecturer didn't think that doppler effect was necessary to explain it.It isn't. It is necessary to consider the doppler effect to answer some of your questions though.
there are plenty of asymmetric situations where there is no differential aging.
Quote from: hamdani yusuf on 06/10/2023 06:59:05Which one?The questions involving what you see when one twin is moving towards you or away from you.
Is it from another thread?