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Everything posted by xyzt

  1. I agree, there was no need for the heavy handed intervention by ydoaPs.. I would expect an admission of not understanding the subject matter and an apology. It is exactly the behavior he criticized me for that he exhibited (to a much greater extent) , especially in the context of his being wrong.
  2. Look, You still don't get it and you are behaving in a manner that is unfitting for a moderator. Let me try to explain one more time (not for your benefit, since you won't admit to error). In the twins paradox (which was the context of the discussion) , with the help of an accelerometer, the twins can tell the accelerating twin from the inertial one. Nice try but this was not the context being discussed. Bill and Bob are the twins, one is accelerating away, the other one is not. There is no "gravitational field". If the twins are stationary, then there is no separation and there is no paradox. I understand that you do not understand, yet you are acting in a manner that is unbecoming for a moderator. Especially since you are wrong. One more thing: don't talk down to me and don't threaten.
  3. Err , I am under the impression that you do not even understand my initial post. It has absolutely nothing to do with being able to tell the difference between the effects of a gravitational field and of acceleration. When I said that acceleration is "absolute" (as opposed to velocity), that means that you can ALWAYS tell, with the help of an accelerometer, if you ARE accelerating or NOT. By contrast, you cannot tell if you are in uniform motion. I made it quite clear: Not very becoming for a moderator. Especially in the context of clearly having misunderstood the post you are attempting to criticize.
  4. If the gravitational field is uniform and if the proper acceleration is constant, the principle of equivalence teaches us that we cannot tell one from the other. If the gravitational field is not uniform, then we have an effect called "tidal" , i.e. there is a transverse "squeezing" of the accelerometer, an effect that cannot be mimicked with uniform acceleration. Thank you for actually asking an interesting , intelligent question that takes this thread out of the cesspool it had descended.
  5. Well, it happens very seldom that I get a honest reply to my criticisms. Normally, I get a crank run-around.
  6. This is the best example of a measured, rational, answer. No attempts at diversion, further elaboration, introduction of further complications, etc. You got my +1 for that. Too bad that there aren't more like you in this forum.
  7. He's been told that (and many other things).
  8. Actually both Delta and I have pointed that out. Repeatedly. Correct. Thank you. Apparently the moderators found my well-intentioned and appropriate suggestion insulting. This forum has turned into a battle between mainstream people and cranks, with a very heavy dose of threads that are fringe. I will be hard pressed to name a thread that was not started by a fringe set of claims.
  9. Everything else that you posted is correct, except the above. You cannot tell that you are in a gravity well. Your clock ticks at the same rate, of 1 second per second. Clocks do NOT 'slow down" in gravity wells, this is an unfortunate, widespread misconception. Clock ALWAYS tick at their native rate, otherwise they would be worthless as clocks. What happens in reality is that when clocks are observed by a remote observer they appear to "slow down" (to an observer "higher" that the clock in the gravity well or to "speed up" , for an observer "lower" that the clock. This is the main reason why the atomic clocks mounted on the GPS satellites need to have their frequency adjusted down at launch: such that their time stamps line up with the time of the Earth bound clocks.
  10. That is false, clocks tick at the same rate all over the universe: 1 second per second. You simply repeat the same misconceptions over and over in a slightly different way. Yes, all observers agree on the age of the universe. This is the second time you are being told that. You seem to have a hard time accepting it.
  11. It is called GiGo (Garbage In , Garbage Out) You must be talking to your mirror again. Keep crank posts to a minimum.
  12. "Assuming that we could teleport instantaneously....". This just only one of the fringe things you posted.
  13. You didn't ask, you asserted. Amongst other fringe claims.
  14. You cannot teleport "instantaneously". You cannot even travel at the speed of light. Neither, if you understood what was explained to you, you would have understood that the the age is still 13.82, speed has no effect. No.
  15. It does happen (in real life, with real scientifically minded people). Not very often in this forum where trolling and time wasting is "du rigueur". Where is the fun in accepting a rational, scientific, rigorous explanation when you could stretch the thread on 10 more pages?
  16. This is not quite right. Bob measures an em ray sent by Bill as redshifted (Doppler). Bill measures an em ray sent by Bob redshifted by the same amount. Nothing to do with total elapsed proper time. Proper elapsed proper time omes into play only when the twins are reunited via some mechanism and they can compare clocks side by side. Dingle mixed the mutual time dilation with the twins paradox. The two are two DIFFERENT effects of SR. Correct. I wrote a big chunk on that page.
  17. I simply pointed out that you lack the basics for tackling more advanced issues. <shrug> No one can travel at light speed. Even if that person did, by absurd, he or she would NOT "age slower". Your quote come from a crackpot website, written by a relativity denier, a well known crank called Nick Percival. You will not learn anything useful from that website.
  18. Wrong. Have you tried actually studying the subject? Wrong again. Bill is also 30 years old. Look, you are grappling with the so-called "Twin Paradox". Understanding it requires a fairly good understanding of special relativity. You do not have that. Here you are struggling with mutual time dilation, or the so-called "Dingle paradox". This is not a paradox , it stems from the lack of understanding of basic SR. The twins "paradox" that you are grappling with has NOTHING to do with time dilation. You have way too many misconceptions about relativity, you should consider a class. Start slowly, from the basics, only AFTER that you can tackle the more advanced subjects.
  19. No, acceleration (proper acceleration , more correctly said) is absolute. You can measure it with an accelerometer, so you know exactly who's accelerating and who's not.
  20. yes, it is called conservation of angular momentum, sorry to burst your bubble, it isn't a new phenomenon
  21. Obviously. His posts are either content free or outright nonsense.
  22. They move in OPPOSITE directions. This DOUBLES the effect. Have you watched the video? Did you bother to read the wiki article on the Coriolis effect? Sigh.
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