Everything posted by Genady
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The twin Paradox revisited
I see. I've replied too fast, sorry. Send your calculations whenever they are ready.
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The twin Paradox revisited
I don't see why their beards would be of equal 'age' at the crossing point. I expect them to be different. One hour ahead of me.
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The twin Paradox revisited
Take your time. I take mine, too. What is your time zone?
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The twin Paradox revisited
I don't think there is a way to consistently synchronize these frames when they are in relative motion and at a distance from each other. You can see it on my spacetime diagram above. Except the starting and the crossing points, there are no points on the B's and C's worldlines, which are simultaneous in B frame and in which the twins are the same age. Specifically, when A sends the signals, the twins are of the same age in A frame, but not of the same age in B frame. If you want, you can show your calculations, and I'll try to point where there is a wrong assumption.
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According to mainstream physics: Is heat "destroyed" in a heat engine?
If I have a flat sheet of paper and then roll it into a cylinder, did the flat sheet disappear, vanish, etc.? Certainly, not.
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According to mainstream physics: Is heat "destroyed" in a heat engine?
In my studies of thermodynamics, I have never seen such expression or its equivalents in any textbook. Then, according to the mainstream physics: No.
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Gravity (split from A change in Gravity killed the dinosaurs!)
These "observations" of weight changes are as reliable as his "observations" of "pulsations" of the Earth movements around the Sun. Do you believe his "data"?
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Gravity (split from A change in Gravity killed the dinosaurs!)
No, it isn't. He was. Where is it? Reference? Citation?
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How far into the future do we care? And why?
You too.
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How far into the future do we care? And why?
The fact that I do something is evidence that I can't do it? How come?
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How far into the future do we care? And why?
The fact that I do is a proof that I can do.
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How far into the future do we care? And why?
Well, you would say that... 🙄 Not only that I can, I also do.
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Theories on quantum geometry and entropy
Pun intended?
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How far into the future do we care? And why?
This is only an evidence that even a full blown monster could have some human - but not exclusively human - things. Repetition. Wrong. Every person, that's survived into adulthood, started with a wide range of capabilities. I don't think I can't see my bias. Maybe. Maybe not. Maybe there are other ways. I can imagine this. I also can imagine a sort of sweet growing up, without any suffering, and also be made to love dogs more than humans. I also can imagine many other scenarios with that same outcome. Of course, he was a human, i.e., Homo sapiens, biologically. I don't think that every supervillain does, but whoever does, it is only evidence that they had what was needed to get the doctorate. It does not say anything else about them. Even about their intellect.
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How far into the future do we care? And why?
It might help if you say it straight rather than via a metaphor. If the thing is, that we are but a product of our environment, then you don't need to repeat it. Repetition will not convince me. If the thing is, that deep inside we are all the same - ditto. If the thing is, that every person is capable of everything - ditto.
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Gravity (split from A change in Gravity killed the dinosaurs!)
Does not seem so: Anatoly Chernyaev. The principle of the golden section (delachieve.com) Yes, independent of science.
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The twin Paradox revisited
Reference to the gravitational time dilation is helpful for a qualitative understanding of what is going on there, but to calculate the effect of the acceleration you don't need GR. It all is computed using SR, although the math is somewhat involved. Here you can find the calculations, and the author also applies them in the general case of two twins with various spacetime trajectories, of which two scenarios considered above - the twins A and B, and the twins B and C - are special cases: acceleration.pdf (uconn.edu) (The Relation Between Acceleration and Time Dilation in Special Relativity, James G. Bridgeman, December 8, 2018)
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"The Balloon !"
They keep coming: US military shoots down high-altitude object over Lake Huron on Sunday | CNN Politics
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I wanted to ask a question so I created an account!
I don't know what it means, to go physically back in time and at the same time not to - As I don't see, how one can think about what is - and at the same time not to - These statements seem self-contradictory to me.
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The twin Paradox revisited
Maybe the most direct way to see what is going on there, is on a standard spacetime diagram. Here I've drawn it on the background of the A's frame, just because it is symmetrical and easy to draw. The analysis is still for the frame of twin B. The vertical black line is A's time axis, and the horizontal black line is A's space axis. But I am not going to refer to them. I will focus on the colored lines. The red line, IJK, is the worldline of B. The blue line, IMK, is the worldline of C. B starts at event I, turns at J, and returns at K. C starts at I, turns at M and returns at K. When B is getting to the turning point J while outgoing on the section IJ, the green line JN is his simultaneity line, i.e., all events on this line are simultaneous with J, for B. So, coming to his turning point, J, B observes C at N, which is quite some time before the C's turning point, M. This is time dilation of C observed by B. Then, B turns around, i.e., switches to the section JK. Now, the orange line JL is his simultaneity line, and he observes C at L, quite some time after C's turning point. While B makes the return trip JK, C makes only the part LK, which is again the time dilation of C as observed by B. The total time that passed on B's clock is, IJ+JK. The total time that passed on C's clock as observed by B is IN+NML+LK. Obviously, because of the symmetry, these two lengths are equal. IOW, they aged by the same amount and cross at K with the same age.
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I wanted to ask a question so I created an account!
Do you mean that you+car's mass went back in time one week? How does it work with the conservation of energy? How can you or anybody know which variables affect or not the result of the rolling? Do the presence of you+car's mass, extra weight on the floor, changed resonance frequencies, air disturbance caused by you+car, etc. affect the result or they do not?
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The twin Paradox revisited
I mean that in the B frame, the change in his observation of C caused by its turning compensates exactly the total time dilation that it observes in C.
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I wanted to ask a question so I created an account!
If this car makes you only a spectator, then how is it different from somebody taking a video of you rolling the dice and then replaying the video a week later?
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The twin Paradox revisited
No, turning of C does not affect B. B just observes C moving with different velocities and calculates the total effect. However, turning of B affects B and its observations. The same in the classical scenario, with A staying on Earth and B going out and returning. Turning of B does not affect A. It does affect B and its observations. We would have to consider the turning of C and its effect on the C observations, if we described the scenario in the C frame.
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Does eating eggs increase cholesterol? What are the latest scientific studies/data suggesting?
Hey, that was my breakfast today. Minus walnuts, orange, and milk, plus peanut butter.