Comments by "Lepi Doptera" (@lepidoptera9337) on "National Geographic" channel.

  1.  @SpaceMan-f6d  The floor is accelerating in the inertial system of test masses on which no forces are acting. You need to pay very close attention to how force is defined here. Gravity is not a force. Never has been, never will be. Even Newton knew that. :-)
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  2. The floor of the elevator is constantly accelerating with 1g upwards. There is a so called "waterfall interpretation" of general relativity that thinks of spacetime as constantly falling into the center of a gravitating mass distribution. The floor that you are standing on therefor has to cause a constant upward acceleration in this "waterfall" inertial system to keep you at a constant radial distance.
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  3. When we die the brain shuts down and the person is gone. Then the body decomposes and becomes nutrients for other creatures. Perfect recycling. No big deal.
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  4. Only in Galilean relativity. In special relativity it would be the first component of a four-vector.
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  5. If you are referring to the attire... that "professionalism" that you are seeing there was invented almost a century earlier as a political protest movement of students in Europe, if I remember correctly. By the period of Einstein it had morphed into boring conservatism.
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  6. He never said it. He wrote it in a condolence letter to the family of a close friend. It was never a scientific statement. It was a statement to help with the grief. You can't even do research on a simple quote? Why did we spend all of this money for your education on you? It was obviously a waste. Please give it back. ;-)
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  7.  @cloudslady3400  I know it was a joke, but you still didn't do any research on it. ;-)
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  8. The equations are not the same. To get from Newtonian gravity to Einstein you have to have good tests for the strong equivalence principle. In Newton's theory m is both an inertial mass and a gravitational charge. Newton's weak equivalence principle limits of how much these masses could differ was around one part in 1000 and that was only possible on dense materials because they didn't have good vacuum technology, yet. Today we have experiments that have tested this weak equivalence principle to one part in 10^15. We still lack observations that extend this to e.g. black holes and it's not clear that it holds for low density (e.g. galaxies or the entire universe), either. If the equivalence principle breaks down for very dense objects or for objects with very low density, then we need a very different theory of gravity that is neither Newtonian or GR.
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  9. The force on the elevator has to be (m_elevator + m_you) * g. The force the elevator on you would be m_you * g. Not sure what your problem is here.
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  10. Dude. We told you what time is when you were like five years old. You could not have been a very smart child if you couldn't remember that "Time is that which the clocks show.". ;-)
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  11. Yeah, but Hermine Granger knows the magic for making time turners. ;-)
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  12. No, you don't. You want a professor who knows better than Einstein. ;-)
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  13.  @MdIrfan-ps7wf  Yes, I know that you can't think. So what? So nothing. ;-)
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  14. That sounds great, except that changing the size of a molecule changes its vibrational frequencies. No such change has ever been observed. ;-)
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  15. Exactly. We invented numerous gods and they are all horrible abominations of the human mind. ;-)
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  16. Newton thought of gravity in the way of a force. Gravity does, however, not behave like a force. It behaves like an acceleration. The problem is simply that Newton didn't understand the actual metric structure of spacetime. He was working in a Galilean approximation, which we now know is wrong.
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  17. Common sense clearly protected you from learning physics, though. Your version of it seems to strongly suggest that you are smarter than everybody else, which unfortunately for you is not the case. :-)
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  18. It is accelerating you against a falling inertial system. This is simply a consequence of the definition of "inertial system". Nature knows nothing about our definitions.
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  19. Time is that which the clocks show. We taught this to you when you were approx. five years old. You were clearly not a very smart child. ;-)
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  20. The Jewish god was invented during the Babylonian captivity, i.e. during the years of 597-538BC.
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  21. Yes, but he didn't mean you. ;-)
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  22. Galileo found more than that. He gave a correct example of the relativity principle. It's called Galileo's ship and basically represents the non-gravitational equivalent of Newton's elevator. In a sense Galileo may have discovered the theory of everything around 1630 with that. He just couldn't calculate the logical consequences of his discovery. That would take close to another 400 years. If I had to hand the price for most important physicist in history, I would probably give it to Galileo rather than Newton or Einstein. Having said that, Kepler and Copernicus may have known about the relativity principle already before Galileo and I have a strong feeling that one may find hints of it in the writings of antiquity. Galileo probably just formulated something that had been floating around more succinctly.
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