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swansont

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Everything posted by swansont

  1. Can we? Yes. Must it happen? No. g=GM/r^2 The gravitational acceleration will depend on how much mass you have, and the configuration. If you have a spherically-symmetric configuration, the gravity at R only depends on the mass inside of R. The effect of the mass outside all cancels out. The gravity inside of a spherical shell is zero. Because the details matter, and you didn’t provide sufficient detail
  2. And Santa is a story that’s not uniform across cultures and the traditions around Santa gift-giving have evolved over time. So yet another example that points out the lack of fidelity of oral tradition
  3. I did see the b/w video, and there was no evidence of anything glowing, no heat plume of a rocket, and no detonation. I would ask about these things. I’d ask to see a video of a normal hellfire impact. I also saw a snippet of the testimony, where a witness said an object was 100 feet away (or something like that) and I would want to know how they determined the distance.
  4. Which is expressly against the rules. I can’t e.g. get an AI to clarify how it concludes that the orb was glowing. If you want to discuss this, upload/link to the video in question, or images, include enough information so it’s not required to watch the video, and don’t outsource the conversation to AI
  5. Someone telling a story is not necessarily a teacher, much like a scribe or stenographer is not an author.
  6. But the words haven‘t changed. We can all refer to a passage and know that 200 years ago, people were debating the meaning of the same passage. Nothing added, subtracted or substituted, without a record of those changes.
  7. The point is that this was an oral tradition before being written down, and it didn’t survive intact over a small number of generations. Another example would be the fairy tale The Smith and the Devil. Many variations exist, partly because language changes as culture changes.
  8. No, no! It’s an adult, obviously, because Donald is quite well known for his attraction to mature women with very small breasts.
  9. I think there is mathematics involved. Error correction would be one concept.
  10. You can’t BS your way past the math. It either works or it doesn’t. You can’t say you support Lorentz transforms but think that length and time are invariant because those statements contradict each other. If it’s not imaginary you have to be show it objectively exists. Being able to imagine something means absolutely nothing, because you can imagine physically impossible things. Nothing controversial about that The photons in space are not connected, nor are they matter, so this kind of connection doesn’t exist. And as has already been explained, if there was some material filling the space between us, it could not be perfectly rigid and signals within it can’t propagate any faster than c. Einstein was shown to be wrong.
  11. I don’t think the US would have any military response. Trump would blather on about how he’s disappointed, how there will be consequences, say it’s actually Ukraine’s fault, and something will happen in two weeks.
  12. It’s required by the speed of light being invariant. Having it not be invariant has implications that can be tested, and the proposal fails those tests. It’s already been investigated, which is why there’s no need to consider it. You don’t have a model. If you did we’d be able to make quantitative predictions and show how they fail to agree with experiment. The equations would allow anyone to investigate the implications rather than having to rely on whatever scenario you fabricate. One problem with redshift/blueshift is that it’s not just signals that get modified. You can move clocks and only compare them when they are at rest, next to each other. They still show relativistic effects. Charge distribution in high-speed nuclei shows length contraction — how does red- or blueshift come into that? Or in muon decay? There’s no EM radiation involved in the latter two.
  13. Evidence? Have you ever played the telephone (aka Chinese whispers) game? https://en.m.wikipedia.org/wiki/Telephone_game Again: evidence? You can at least compare the current version with the original, which is impossible with oral transmission over many generations. As I’ve said.
  14. I don’t see how that makes it a property.
  15. But this is a discussion forum, not a blog. Can it be controlled? No. Can it be predicted? In a limited way, possibly. The strange attractor phenomenon you briefly mentioned. But there are limits to how precise our data can be, so there are limits on what can be predicted when the results have a (possibly complicated) nonlinear dependence on initial conditions.
  16. In the spacetime interval example, it could be describing two events. It’s a system only because we describe it as such. Events don’t have to be related
  17. Random is being used because it’s in the source text (which I noted lacks rigor) and answers are being provided in that context. Which is why I wanted the source. Context is almost always important when there’s confusion surrounding a short snippet of quoted text.
  18. Who told you that nature has any respect for or acknowledgment of your common sense? The conclusions we draw are in the framework of the best models we have. If you want to interpret them in terms of another model, feel free to present it. But all of the evidence that’s covered by the model has to fit, and contradictions must be addressed. “Common sense” is not a model and given its spectacular failures, it does not get a seat at the table. “Common sense” tells us that the earth is flat, the sun (and almost everything in space) orbits the earth, heavy things fall faster. Some people think the position of astronomical objects influence our fate. Some think black holes exert more gravity than other objects of equal mass. That the seasons are caused by the distance to the sun varying. Common sense suggests there is no gravity in space. What examples can you give, and what experience do you have that you can say what happens “often” in science? We (well, most of us doing advanced physics) know when this matters and when it doesn’t. Partly because we quantify things, because we have equations, and know the importance if significant digits in calculations. It takes more than the assumption. You need to actually show the premise is false and/or what the missing variable is, or at least provide a compelling argument that there’s something missing (as we did with the neutrino and do with dark matter)
  19. It’s invariant in inertial frames (everyone agrees on the value), but not if the observer is accelerated. You could account for it, I suppose, much like adding in pseudoforces lets you apply Newton’s laws Agreeing if you’re in an inertial frame. Rest mass and charge, too. Any invariant quantity. But the interval is not a property of an object, as such. It’s a value for two events.
  20. So it’s https://ncert.nic.in/textbook/pdf/kech105.pdf page 159 (I’d quote but the text is copy-restricted) You should read the part before that to add some context to it, where it talks about the randomness of molecular motion. Unfortunately the explanation isn’t quite as rigorous as it should be, but temperature is related to the average KE of the random motion of the molecules, and KE = 1/2 mv^2 So adding a set amount of heat does not increase the motion in a linear way. i.e. if you double the temperature, v does not double. The motion is affected more at low T.
  21. Which is abject nonsense. Even traveling close to c, the ship will arrive after a light signal that leaves at the same time. The only data it will arrive before is data that was transmitted some time after the craft left. If the craft is transmitting, that data will beat data from earth because it doesn’t have to travel as far, but there’s nothing that should be surprising about that. If the craft is relaying data from earth, no advantage is gained because it takes time for the signal to get to the ship. Nothing beats the light signal emitted at the beginning of the trip. (You can’t assign a single time to a “constant data flow” since it is not transmitted nor received at one time.) You can’t assume your understanding is correct and deform relativity to fit everything together.
  22. You could also memorize a story about an event, but not fully understand it, so would not notice if you didn’t retell it quite the same. Or omit something you deemed unimportant, or added some embellishments to get a better response from your audience. Which is why one can’t trust that oral tradition gives a faithful account of what the original story was.
  23. It’s not mere disagreement. Physics tells us both of our observations are correct. The abstract existence of the property, in general, is what we can agree on. KE, for example, is a property that is real and not an illusion. The value that it has, though, is not real in this same sense.
  24. What’s your definition of real? Do you mean real as in not an illusion, or real as in physically exists rather than being conceptual? Can a frame-dependent quantity be considered real? Can it be real but lose that designation because someone is accelerating?

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