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Showing content with the highest reputation on 09/24/22 in Posts

  1. Probably something to do with this:
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  2. Is SFN galactose intolerant? šŸ˜€
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  3. Action and reaction implies causality, which implies information transfer. Which is impossible. Correlations, OTOH, have no such limitations. Your definition is a non-starter. Maybe we need to define 'action/reaction' and 'correlation' as well, as we seem to be confusing their meanings/implications.
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  4. This is not a definition. It works for you just because --no offence-- you seem to have very low standards on what constitutes a definition. "Spooky" is not a physical term. If you paid even the slightest attention to the mathematical formalism of quantum mechanics, you would understand this perfectly, as both any "blips" of information, or any "blips" of energy would have to travel in the form of "blips" in the square of the absolute value of the wave function --or the square of the gradient too, in the case of energy. That's what the quantum dynamics doesn't allow to do superluminally. (quoting your quote) Yes. Therefore => there can be no non-local interactions. Maybe we would have to go a step down and discuss what an interaction is. You say things like, What? The interaction is not physical? What is it then? Metaphysical? Because I'm keenly aware of the dangers of letting hidden assumptions slip into your arguments, I've found that it may be useful to strip the ideas to their bare minimum, and say only what they say, and nothing more. What comes next is a sketch of the history of these ideas. This is in order to satisfy @Eise's demands that we be clear. EPR: If you can predict with absolute certainty the result of an experiment without in any way disturbing the system, there must be some element of reality underlying it. Quantum mechanics says that certain pairings of observables are incompatible, say A and B. If I can exploit a conservation law that's valid for at least one of them, say A, in a bipartite system (A1+A2 = constant) and measure A in part 1, and B in part 2, I can infer what the value of A2 is without actually measuring it. I can, at the same time (within a space-like interval) measure B for 2, that is B2, with as much precision as desired, and I would have proven that quantum description of reality is incomplete, because I would have the values of A2 and B2, which quantum mechanics declares as incompatible. In a nutshell: Either quantum mechanics is incomplete, or your wave function would have to be updated superluminally, to make this incompatible character of A and B persist. I hope that is clear. If it is, we can all jump to the same page and proceed to Bohm, CHSH-Bell, Aspect. That means: why Bohm shifted the discussion to spin, what do the CHSHB correlations say and don't say, and what Aspect actually found. Then, perhaps, a discussion of science as perceived by the masses as well as relatively learned non-experts, and why this non-locality nonsense proves to be so persistent, the very same way that thousands and thousands of claims of possibilities for perpetual motion kept coming long after the question of its impossibility was perfectly understood by the theorists.
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  5. Iā€™m not sure we differ on this - I completely agree that you can choose whatever type of diagram in whatever coordinate system is most useful for the particular problem at hand. Thereā€™s no right or wrong way, only usefulness and its opposite. Thatā€™s precisely the beauty of GR - the physics do not depend in any way on how you label and depict events in your spacetime. Labels donā€™t have physical significance, only the relationships between them do. There are just two points that need to be borne in mind: 1. A choice of coordinate system generally (not always) corresponds to choosing a particular observer, so it will reflect how that specific observer evaluates the situation using his own local clocks and rulers. This is very important, since notions of space and time are purely local, so different observers will differ on these without creating any physical paradoxes. Theyā€™re bookkeeping devices - like accountants using different currencies may come up with different-looking books for the same company. In particular, Schwarzschild coordinates (irrespective of where you place the origin) physically correspond to a far-away observer at rest, and will thus reflect the far-away stationary notion of clocks and rulers. For obvious reasons, if you plot null geodesics on a chart using these coordinates, they will never reach or intersect the horizon on that diagram (!!!). Iā€™m highlighting and exclamation-marking this to point out that such a diagram is observer-specific and reflects only what this particular observer calculates using his own local clocks and rulers. 2. There is no rest frame associated with photons, so, unlike is the case for time-like geodesics, you cannot parametrise photon geodesics by arc length (=proper time), since ds=0 by definition. Instead you can use an affine parameter of your own choosing. I completely agree, especially since we already know that our usual paradigms donā€™t work for this. In particular, I suspect that any notions of smooth and regular space, time, spacetime with well-defined causal structures, and fields on spacetime will become meaningless in the realm of quantum gravity. Physics there will deal with dynamical quantities that are very different from those of ordinary classical physics, or even those of quantum physics, which will likely change the way we think about reality in very fundamental ways. I hope I will get to see it in my lifetime, but itā€™s possible that we are still a long way from such a model. Thereā€™s no way to tell, really.
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  6. Methylene blue can be used as a rinse to clean off nets, When I ran a petshop I kept methylene blue in containers near the fish bagging station to keep nets soaked in why waiting to be used. I've also used peroxide in the net dip containers and I use peroxide to clean equipment like filters and other accessories. Drying the plastic parts out over night will remove the peroxide. "in the aquarium" is tricky, most people would use antibiotics instead of disinfectants, few disinfectants are any better at killing bacteria than they are at killing fish. Palmolive or any soap is a bad idea in aquariums, it's difficult to really rinse off but it's deadliness to aquatic life is less than it used to be but still not low enough to be used in an aquarium.
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  7. Could be Snowman rolled 'er, over.
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  8. Non-local interactions have been demonstrated as ā€œrealā€ in both theory and practice so I donā€™t understand the futility of explaining why there is no such thing. That reminds me of the mathematician long ago who published his calculations about the very minimum size for a functional radio coil. Unknown to him, a radio experimenter had already patented a working radio coil that was far smaller than his theoretical limit. This is still happens now. Mathematicians calculate the minimum size of an IC junction but the manufacturers donā€™t care. They they keep designing working chips that are smaller and better than theory allows. As Feynman said about ICā€™s, ā€œThere is room at the bottomā€. You and others may have equations where what appears to be non-locality is really local but there are others such as John Cramer who showed how the mathematical formalism of QM can be interpreted in terms of direct interaction (non-local) between emitter and absorber. Hugo Tetrode did the same in 1922. If you can site some physical experiments that demonstrate what you are saying, you have my attention. I donā€™t know of any such experiments but there are many that demonstrate non-locality. Yes, it does but the interaction is not physical. In TIQM a "photon" is not a space traveling, energy carrying particle. A 'photon' is Cramer's name for the single quantum of energy involved in the transaction.
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