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Duda Jarek

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Everything posted by Duda Jarek

  1. But the claim "it doesn't work to explain the observations. " needs doing some analysis of this possibility - where is this analysis? If there is none, means this possibility was neglected - excluded without even trying.
  2. The main question to discuss here is if without Einstein we (or some other civilization) would get to GR. Alternative way is introducing succeeding terms of Taylor expansion of GR - the question is what could be the "extraordinary evidence" to convince that it is necessary to introduce intrinsic curvature of spacetime in non-renormalizable theory (GR). Finally some experiments, so let's discuss them: - from https://en.wikipedia.org/wiki/Tests_of_general_relativity : so it is mainly about gravitoelectric effects - isn't it part of GEM? Imagine analogous EM situation: circulating charge produces magnetic field, which leads to Lorentz force precessing the orbit. I don't know why they didn't use Heaviside? Maybe they just were not aware (?), he is not mentioned in https://en.wikipedia.org/wiki/Two-body_problem_in_general_relativity It seems Heaviside's paper had one citation before 1950: https://scholar.google.pl/scholar?hl=en&as_sdt=2005&sciodt=0%2C5&cites=5741552482440482063&scipsc=&as_ylo=1800&as_yhi=1950 Anyway, if Heaviside's GEM is approximation, then just use the proper one from Taylor expansion of GR. - regarding light bending, we observe it also e.g. in water - due to different propagation speed. Without Einstein one could use this explanation - requiring some slowing down of EM propagation in gravitational field - some coupling between EM and gravity. These are low field effects - can be explained by using a few first terms of Taylor expansion of GR - one could estimate/use them not being aware of complete GR. I am afraid that to get to really convincing arguments, we would need to go to high field effects - like distinguishing neutron star from black hole - how such argument could look like?
  3. Sounds like "neglected possibility" as I am writing - one question is why? (I would say that due to proton decay nonobservation in water). Second question is if it really should be neglected without real consideration?
  4. Indeed - for papers discussing proton/neutron decay possibility to understand energy sources we cannot explain in standard way. I couldn't find any (?)
  5. To know whether a possibility is useful, it needs first to be considered - the problem is that it seems this didn't happen (?).
  6. What do you base that on? https://en.wikipedia.org/wiki/Proton_decay says proton -> positron + pi0 and pion further decaying to gammas, which from energy conservation need to carry ~1GeV energy in this nearly complete matter->energy conversion. I am saying saying "baryon decay" because such matter->energy conversion would also concern especially neutrons. There are many astronomical objects they say with orders of magnitudes higher energy production than can be explained, but I didn't see hypothesizing baryon decay (?) Yes, I am referring to baryon number non-conservation: as proton/neutron decay into non-baryons.
  7. Because baryon decay would be nearly complete mc^2 matter -> energy conversion. If happening in core of neutron star, it could greatly increase energy production - above what we can explain without it, and there are observed such unexplained examples. How many nuclear fusion events should they expect in all these proton decay experiments?
  8. Indeed charge conservation is quite different from baryon/lepton number conservation. Regarding "the same way it disprove nuclear fusion", I have only meant that fusion also don't happen in room temperature water, but we shouldn't conclude that it disproves fusion - which requires much more extreme conditions. However, unobservation of proton decay in room temperature water is often seen as disproof, made it an exotic concept not worth considering. Regarding hypothetical confirmation for astronomical objects, if it would happen in one of the most extreme places: core of neutron star, we wouldn't have a chance to see some additional spectral lines, only excessive energy, like this "1,000 times brighter than researchers previously thought was possible for neutron stars " of NGC 5907 X-1.
  9. Where??? There was some criticism of GEM, which accordingly to a few Wikipedia articles like https://en.wikipedia.org/wiki/Gravitoelectromagnetism was confirmed by Gravity Probe B, its examples are frame dragging, Lense-Thirring. But if you have some allergy to this well established GR approximation, then just take a few first terms of Taylor expansion of GR - low field approximations, which are used for calculations for most of these experiments Without Einstein they could be seen as found succeeding terms added in Lagrangian - like they did for Standard Model (maybe also first Taylor terms of some TOE?) Please elaborate how without Einstein one could extrapolate from these terms that we need to introduce intrinsic spacetime curvature in non-renormalizable theory?
  10. If baryon decay would happen inside some neutron star, the basic observed consequence would be larger energy outcome ... like "This extremely dense object is 1,000 times brighter than researchers previously thought was possible for neutron stars (...)" from https://www.space.com/35846-brightest-farthest-neutron-star-discovered.html So the question is if astrophysicists should have baryon dacay in "bag of possibilities to consider" - and it seems currently it is completely neglected, I would say that due to general belief that it was disproven by unsuccessful search of proton decay in water tanks ... which is misunderstand as the same way it "disprove" nuclear fusion. We rather don't have doubts that electric charge has to be ultimately conserved - due to Gauss law making all field guards its conservation, analogously to topological charge. But for baryon number we don't have anything like this.
  11. Extraordinary claims require extraordinary evidence - there is a lot of general talk here, but I am asking about some details: convincing experimental evidence and argumentation. Imagine civilization without Einstein: weak field effects can be introduced "the Standard Model way": as sequence of corrections - first terms of Taylor expansion of GR. What experimental evidence could be used to convince them that spacetime is not flat but needs intrinsic curvature: that only non-renormalizable GR can explain it? There are needed strong field effects e.g. using black holes - but how such argumentation could look like?
  12. Indeed, hence it is extremely important to reflect what of it really comes from nature - is universal, should be also found by hypothetical other civilizations ... and what is just an artifact of physics being a social construct, for example evaluating concepts based on number of articles people can write about them - this way promoting exciting solutions and forgetting the simple ones.
  13. While I agree that it might be practically impossible to verify it, I have asked if it might be already happening there - these are two separate questions, and I wouldn't be surprised if the answer to the latter was positive. But maybe it could be tested through some Monte-Carlo by adding hypothesized Feynman diagrams into considered ensemble? But if considered for BH, they are created by collapse of neutron stars, many of which have extreme rotation (with some fluxes, shockwaves etc.), with orders of magnitudes higher brightness than what we can explain ... but baryon decay possibility seems completely neglected for neutron stars - should we be so certain about it?
  14. Having GEM in analogy to EM, which was known 20 years before GR, gravity in QFT can be made analogously to EM - through photon/graviton exchange, e.g. with additional summation over alpha=0,1,2,3 as you have written ... so after Higgs they might be confident of having (renormalizable) theory unifying all the forces. While I don't see how the above could lead to acceptance of non-renormalizable theory, the strong field regime might (?) Using GEM instead of GR, such hypothetical civilization wouldn't be aware of black holes, probably expecting heavy neutron stars instead ... what might convince them that it just wrong?
  15. Marcus, the experiments in https://en.wikipedia.org/wiki/Tests_of_general_relativity use low order corrections if seeing GR as Taylor expansion - a civilization without Einstein could be just adding such succeeding terms. Extrapolating to GR from such corrections seems quite nontrivial and might be tough to accept due to non-renormalizability for a civilization which had developed QFT first. For really convincing arguments we should rather think of qualitative consequences for intrinsic curvature, like black hole horizon or wormholes ...
  16. "Can baryon number be violated" is one of the most fundamental questions of physics, it seems we still don't really know answer to (?) Indeed it seems necessary for hypothesis that our Universe has started from a single point, but there is alternative of fixed baryon number of the Universe as kind of additional constant, in Big Crunch preceding our Big Bang. So do we have any chance to answer this question in some future? - what could be accessible convincing experiment? Could it already be happening in LHC? Be accessible in some future colliders? If so, could it be verified there? If not, what about astrophysical possibilities like neutron stars, GRBs with orders of magnitudes higher energies than what we could imagine? ... or Hawking radiation which finally turns baryonic matter into massless radiation ...
  17. For a few decades they have unsuccessfully searched for proton decay in room temperature water, what seems interpreted as disproof of this possibility ... but is it really? The same way we could "disprove" nuclear fusion as it practically doesn't happen in room temperature water ... but happens in extreme conditions. So maybe it didn't disprove baryon number violation, only it needs extreme conditions e.g. to get into some higher energy state before decay? Baryon number violation is hypothesized in baryogenesis, Hawking radiation - which need quite extreme conditions. It is required in many models like supersymmetric, or now popular sphaleron. How can we verify this possibility? Talking with particle physicists, they say we just cannot know if it happens e.g. in LHC, checking baryon number is practically impossible there (?) So maybe astrophysical objects to understand orders of magnitude higher energies than we can explain in standard way? For example https://www.space.com/35846-brightest-farthest-neutron-star-discovered.html
  18. 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 ...
  19. 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".
  20. ... and approval for military use in China:
  21. 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.
  22. 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
  23. 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?
  24. 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?
  25. 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?
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