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Genady

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Everything posted by Genady

  1. No, I don't call approximations, myths. They are different things. Is it an approximation to say that all life forms were created at once from scratch?
  2. Checking with the physicists here: On the p.17 it says, Shouldn't it say force rather than potential? Isn't any potential rather quadratic close to equilibrium?
  3. OTOH, if you are male, you have X and Y chromosomes, while if you are female, you have only one X, since the other X gets inactivated (see Barr body).
  4. The other myth is, for example, that the Hawking radiation is result of virtual pair production when one of the virtual particles becomes real. I've found this article that tries to straighten some misconceptions: Sabine Hossenfelder: Backreaction: Hawking radiation is not produced at the black hole horizon.
  5. After a further contemplation. It appears that I was wrong anyway.
  6. Yes, I certainly agree with this.
  7. To clarify the analogy in my previous post. I don't mean that QFT is like GR, nor that SM is like LCDM. I mean that SM relates to QFT like LCDM relates to GR.
  8. I'd refer to the following analogy. QFT is like GR when SM is like LCDM. GR can fit many different cosmological models, and the open questions are about actual contents and history of the universe, which are the aspects I refer to as being "in addition" to the GR framework.
  9. QFT is a framework that fits models with massive as well as massless neutrinos, with one as well as five generations of particles, with photons as well as phonons, with vacuum as well as solid state, etc. I mean that all the missing questions are specific to the model, i.e., SM, and are in addition to QFT.
  10. Are these QFT or rather SM issues?
  11. Schwarzschild metric and all related derivations such as photon sphere, are valid in vacuum. If we start adding a significant amount of energy there, we need to consider a different metric and different effects.
  12. Pick any: Calculate Pi with Python - GeeksforGeeks
  13. There are many formulas and algorithms for calculating \(\pi\). See, e.g., here: Approximations of π - Wikipedia
  14. Let "result" to be a b's digit of the number \(\pi\). I don't know it beforehand, but they will be equal.
  15. So, what is wrong with defining, say, result1==result2==5?
  16. I remember that charged particles moving in rotating magnetic fields are involved in the description of this, but it was too long ago (and not in my main line of study) to recall details. Hope to see some expert answers.
  17. Philosophy is certainly neither pseudoscience nor science. It is also not football, chess, music, engineering, cooking, etc. I think that "love of wisdom" is a good definition.
  18. Well, the instantaneous change of acceleration, in the case of circular motion, happens to be also "along the direction of motion, perpendicular to the instantaneous acceleration". However, I don't know how they (i.e., the time derivative of acceleration and the radiation) are related and don't claim anything in this regard. My point in this post was that AFAIK, a constant acceleration of charged particle can be insufficient to cause radiation.
  19. The direction of the acceleration changes. The vector rotates.
  20. Something is missing in this definition. As it is described, the simple solution would be just to have a "result" some constant or, more generally, independent on the variable "a".
  21. It is not. It is an example of not every acceleration resulting in radiation, i.e., in these examples a changing acceleration results in radiation.
  22. AFAIK, not every acceleration causes radiation from a charged particle. For example, in synchrotron radiation the acceleration is perpendicular to the particle velocity. In some other cases, a magnitude of acceleration is variable. Is it correct?
  23. Are they? Don't they collide with each other and affect each other non-gravitationally?
  24. If the light orbiting the BH is not a test particle but rather has the energy as described in the OP, then I think it is not on a photon sphere anymore. The "photon sphere" of the original black hole would be inside the new black hole.

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