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Duda Jarek

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About Duda Jarek

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  1. General relativity has this huge problem of being non-renormalizable ... while it wasn't an issue when it was introduced, a few decades later it would make GR extremely difficult to accept - there would be needed very strong experimental evidence to give up renormalizability - which experiment could it be? GR can be seen as a sequence of corrections in Taylor expansion - without Einstein we might now slowly introduce such succeeding terms ...
  2. But mathematically GEM is also Maxwell, can be analogously realized with Lorentz invariant F_munu F^munu in Lagrangian ... why do you think it cannot be Lorentz-invariant? Exactly! GR has renormalization problem as e.g. Feynman ensemble of all shapes of specetime leads to "larger infinities than usual" ... In contrast, flat spacetime GEM is just second F_munu F^munu in Lagrangian - is trivial to unify with the rest of physics, renormalize. Without Einstein, a few decades later a non-renormalizable concept would be nearly impossible to accept (needed extremely strong evidence), definitely more difficult than adding new terms/corrections to GEM to repair experimental disagreements, like in the "Standard Model way".
  3. ... and approval for military use in China:
  4. Also China and probably others ... and minimizing e.g. expected number of casualties, this might be a reasonable behavior. Personally, if having opportunity to participate in such test, if only not having some nasty side effects, I don't think if I would have any doubts.
  5. https://www.bbc.com/news/world-europe-53735718 Coronavirus: Putin says vaccine has been approved for use Two more Stage III (8, +1 "approved") in https://www.nytimes.com/interactive/2020/science/coronavirus-vaccine-tracker.html
  6. I have just added: https://en.wikipedia.org/wiki/Frame-dragging starts with "More generally, the subject that deals with the effects caused by mass–energy currents is known as gravitomagnetism, which is analogous to the magnetism of classical electromagnetism. " https://en.wikipedia.org/wiki/Lense–Thirring_precession starts with "It is a gravitomagnetic frame-dragging effect." I still don't know where do you see a disagreement?
  7. This article starts with below diagram with caption "Diagram regarding the confirmation of gravitomagnetism by Gravity Probe B" - which is this second set of Maxwell's equations. https://en.wikipedia.org/wiki/Frame-dragging starts with "More generally, the subject that deals with the effects caused by mass–energy currents is known as gravitomagnetism, which is analogous to the magnetism of classical electromagnetism. " https://en.wikipedia.org/wiki/Lense–Thirring_precession starts with "It is a gravitomagnetic frame-dragging effect." Where do you see a disagreement?
  8. Most of them directly use GEM, like Gravity Probe B - please specify experiment and we can discuss it. This question is not only "alternative history", but also many e.g. in SETI hypothesize existence of other civilizations - it might be worth understanding if their physics would be based on GR, or maybe on adding corrections to GEM - which might asymptotically reach GR? Not having Einstein, which experiment could convince e.g. them that it is necessary to give up flat spacetime and introduce intrinsic curvature?
  9. But which experiment would bring certainty that we need to give up flat spacetime? From https://en.wikipedia.org/wiki/Tests_of_general_relativity : - Perihelion precession of Mercury is GEM: "Gravitoelectric effects" + Lense–Thirring precession - Deflection of light by the Sun - would need some EM-GEM coupling: slowing down of EM propagation in presence of gravitational field, - gravitational time dilation - clocks are usually based on EM propagation e.g. in atoms, so slowing down of EM would slow down clocks ... the question is other interactions: what do we know about gravitational time dilation e.g. for muon decay? - Gravity Probe B tested GEM, - gravitational waves - also in GEM ... ... black holes - sure we have objects of extremely high density, but how to distinguish what is happening inside?
  10. Indeed special relativity did not require Einstein, as it was already e.g. in EM/GEM Maxwell's equations. General relativity introduced intrinsic curvature of spacetime, while earlier it was thought to be flat. So which experiments bring certainty that spacetime is curved? Sure we need it e.g. to bend photon trajectories, but looking e.g. at glass of water reminds that there are also other ways to bend photon trajectories - like some slowing down of EM propagation in presence of strong gravitational field here (some EM-GEM coupling), what would also lead to some gravitational time dilation effects.
  11. A valuable thought experiment from neighboring thread - how would physics develop if there would be no Einstein, especially regarding gravity? While modern physicists might say that without him there would be "weeping and the gnashing of teeth", his introduction of general relativity a century ago seems to be event of extremely low probability (?) - so what if it wouldn't happen? Or imagine some hypothetical other civilization e.g. SETI is looking for - would it automatically get to GR? If not, how their physics would develop? Beside Newton's gravity, there was also known GEM before ( https://en.wikipedia.org/wiki/Gravitoelectromagnetism ) - just take Maxwell's equations to gravity, making it Lorentz-invariant theory. "The best confirmation of GR": Gravity Probe B in fact has confirmed GEM as approximation of GR. Without Einstein we would probably develop further Heavisides' GEM - adding corrections to Lagrangian (like in "Standard Model approach"), starting with EM-GEM coupling to bend photon trajectories by Sun ... the big question is if gravitational time dilation could be explained by such slowing down? GEM has no renormalization problem, trivially unifies with the rest of physics as it is just another F_munu F^munu in Lagrangian - many approaches to solve this problem like string theory might never appear (?) Where the problems would start - which experiments leave no doubts that we have to use GR instead of GEM? Which cannot be repaired with added terms to GEM Lagrangian?
  12. It would be interesting to derive (and confirm) general relativity corrections to Jefimenko equations ... Many GR confirmations like Gravity Probe B are in fact of GEM - what confirmations of higher order terms are there? GEM was introduced by Oliver Heaviside in 1893 and is Lorentz invariant ... interesting thought experiment: how physics would look like without Einstein? I believe they would build on GEM - adding corrections to Lagrangian, starting with EM-GEM coupling to bend photon trajectories by Sun. GEM has no renormalization problem, trivially unifies with the rest of physics as it is just another F_munu F^munu in Lagrangian - many approaches to solve this problem like string theory might never appear (?) Where the problems would start?
  13. Looks like GEM approximation of general relativity (confirmed e.g. by Gravity Probe B): https://en.wikipedia.org/wiki/Gravitoelectromagnetism You can use standard methodology/tools from electromagnetism for that, like avoiding PDEs with Green's function e.g. in static https://en.wikipedia.org/wiki/Biot–Savart_law or general https://en.wikipedia.org/wiki/Jefimenko's_equations ps. Kepler problem simulator using this approximation: https://demonstrations.wolfram.com/KeplerProblemWithClassicalSpinOrbitInteraction/
  14. Sure, it is also possible that there are teapots flying throughout the Universe ( https://en.wikipedia.org/wiki/Russell's_teapot ). While we cannot exclude unimaginable amount of stuff, a practical rule to get anywhere is Ockham's razor ( https://en.wikipedia.org/wiki/Occam's_razor ) : "entities should not be multiplied without necessity" - before going to "exciting explanations" (loved by the bibliometric evaluation system), really explore the the nonmagical ones first.
  15. So you agree or disagree? Such hypothetical "increased probability in presence" can be alternatively written e.g. as positron + gammas + proton-> 2 protons electron + gammas + antiproton -> 2 antiprotons with some exchange in Feynman diagrams with this additional particle (e.g. electron, proton, neutron). Our knowledge about violation of baryon number conservation is practically zero - couldn't observe any, which reason might be trying to get proton decay in room temperature, while it is hypothesized for muuuuuch more extreme conditions like baryongenesis or Hawking radiation (so maybe also center of neutron star?) My point is only that CPT violation is not necessary to explain domination of matter - other ways are e.g.: - fixed baryon number of the Universe - in Big Crunch preceding our Big Bang, - statistical symmetry breaking - some positive feedback mechanism like above, making "the more of one type, the easier to get even more" - finally leading to domination of one type, which initially could be chosen at random, analogously to chirality of life. ps. Regarding claim that proton decay is impossible because we couldn't observe it in room temperature water - we could disprove nuclear fusion in the same way ... some processes just need much more extreme conditions, much more for baryon number violation than for fusion.
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