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joigus

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Everything posted by joigus

  1. I don't think it's that weird. Human language has developed mainly out of inter-human interactions and immediate relations with the natural world. Why would Nature's 'deepest' rules be amenable to description by a code developed in order to talk about concepts such as food, warm and cold, mother in law, etc? What good is 'zero' to a hunter-gatherer?
  2. joigus

    Beecee

    I did notice, and I did wonder if it had any relation to that. It didn't look to me like there was a connection, but I don't remember why. Overall, I think his contributions were more on the side of being very much appreciated around here.
  3. You should avoid identifying common notions like "emptiness" with mathematical ones ("zero") too glibly. You would think, eg, that "nothing" or "emptiness" (the vacuum perhaps?) corresponds to the zero state vector in quantum mechanics, when what the theory tells you is that the zero vector is non-physical. All physical states have measure one.
  4. I don't know about "real" or "artificial." I do know that in classical dynamics or quantum mechanics, energy is a parameter that gets fixed by the initial conditions. You take, eg, one pendulum of a given mass and length. That's your system. You chose the magnitude of either an initial kick, displacement, or combination of kick and displacement. That determines the history. The situation of the parametrics in GR is completely different. You don't fix one energy and get a subsequent evolution. The theory tells you that the energy --the Hamiltonian, as we call it if we hold any hope that the theory will be made consistent with quantum mechanics-- must be identically zero. This is a common feature of all theories that are "insensitive to deformations of the coordinates," otherwise known as "diffeomorphism invariant." It's kinda puzzling, I know. I encourage you to look up: "diffeomorphism invariant theories have zero hamiltonian" on Google search. And there you go: https://arnold-neumaier.at/physfaq/topics/diff.html
  5. Energy conservation is not universal. Energy conservation only holds if 1) The system can be described by a Lagrangian; and 2) The system has time-translation symmetry. This means that the Lagrangian changes only by a surface term when we apply a time translation. As another member has pointed out before: Also, I see no reason why a universe that's just popping up into existence --from a purely physical POV-- should be time-translation symmetric. Conservation of energy for mechanical systems can help you solve the equations of motion. Conservation of energy in GR, OTOH, comes from some kind of tautological consistency condition. You can call it a conservation law, if you want, but it doesn't play by the same rules. This "energy" no longer is our trusty old mechanical energy, but a related construct that includes dynamical, geometric, and vacuum terms. All the terms must add up to zero by definition. Not sure it can be used as any kind of predictive tool.
  6. There is no such thing as an all-encompassing scientific argument. Sure. I think many of us here are familiar with the fact that some extremely unscientific disciplines are very difficult to dismiss completely.
  7. That's a fair point, although the words "in principle" are essential here. Garden-variety BHs would destroy in-falling observers with their terrible tidal forces, accretion disks, etc. Also, I see as an essential part of science, particularly when it comes to testing, the possibility of reporting your results to other scientists. It remains possible, for example, that there is an afterlife, and that most people that ever existed know about it already. This kind of discourse, while logically tenable, does not constitute experimental science IMO. There are very good questions that are not scientific questions. They belong to what I like to call the world of the tantalising.
  8. Indeed! I also have concerns having to do with operationalism. I don't think ideas like this and the like (is there a universe in an electron?) can be tested.
  9. joigus

    Beecee

    I've been wondering for a while too.
  10. No, no.
  11. Photons make things visible, but cannot be seen themselves. They are neither here nor there, although they make detectors go 'click' here or there, and they cannot be thought of in any intuitive way. 'Touching' makes no sense for photons either, since they easily go through each other, unless at so high an energy that non-linear effects of quantum electrodynamics appear, and then they would start scattering off each other. The expression 'lit photons' makes no sense.
  12. Your issue is a non-issue. You don't make any sense. You never do, nor do you seem to care. Having an infinite element (in a particular sense that in the case of natural numbers is clear, and identifiable with a norm) or having infinitely many elements in a set (cardinality), or having a measure of a set are different things. You are --deliberately or not, I don't know-- confusing whether an element is finite (norm?) with how many elements there are in a set (cardinal?), or perhaps a measure (some concept of "extension" or "volume"). One way or another, several members are trying to help you grope towards these important concepts in mathematics, but you don't seem to care, and keep demanding them to address your silly "analogies." BTW, @wtf's last comments go in the direction of your pretence confusion.
  13. Conservation of charge, baryonic number and leptonic number insist that it be so. There are no quarks with charge +1, lepton number -1, and baryon number 0.
  14. That should be your first clue. Usually, the more I look into anything, the less strange and complicated it seems. And that's how it should be. Don't you think?
  15. At the root of it all, I think, is @Boltzmannbrain's remarkable inability --or stubbornness to not recognise-- the limit operation, which in common language is captured by the words "and so on." That is, 1 1, 2 1, 2, 3 and so on. Don't look now BB, but these are the words you're having a problem with. Embrace infinity.
  16. I think they go very much in the direction I was suggesting...
  17. True. But every theory does need to introduce non-observable elements. Examples are the wave function, the gauge, and perhaps the vacuum too. It seems like we're forced to use these 'precursor' concepts that take part in the logical scaffolding of the observable level, but are not exactly on the observable level.
  18. I would say it's not that unusual. Beyond life, but perhaps including the concept of life, we have this one of self-organizing systems. When you have open systems through which a flux of energy is going, you can have order spontaneously appear: https://en.wikipedia.org/wiki/Self-organization
  19. You beat me to the punch on this one. If I remember correctly, the mitochondrial membrane is mighty selective about what side of the membrane the protons are, which is essential to the workings of ATP synthase, but not so much about where the ATP molecules are. This selective permeability --aided by membrane proteins-- can work wonders in setting mechanisms for 'this kind of energy goes here, that kind of energy goes there' mechanisms. Why those are essential for life I think is very compelling.
  20. It's a subtle matter. There's a lot of discussion on the web. When we introduce the so-called bare vacuum in QFT --which is the vacuum state before it's 'dressed' with virtual particles--, we declare it to be invariant under Lorentz transformations. This is more of a formal requisite than an observable, clearly-established operational verification. It plays a big role, if I remember correctly, in axiomatic quantum field theory --Wightman et al. Funny things happen to the 'dressed' vacuum or 'physical' vacuum when you change the frame of reference. On an accelerating frame, eg, a temperature appears. Is that supposed to mean something measurable? I simply don't know. Somewhere else on these forums @Markus Hanke --one of the local experts-- has expressed concerns about what all of this means, with which I very much concur. My personal opinion is that we should have an appretiation of aspects like these, not necessarily in the sense that they mean something about the world, but in the sense that they mean something about limitations, clues, etc, concerning the status of the theory concerning the world. How do you measure anything about the vacuum in a laboratory?
  21. IMO, yes. Keeping some approximately fixed --or stable, or slowly-varying conditions-- anywhere somehow amounts to setting loci of free energy, or available energy, which in turn amounts to resisting entropy. In my mind, that makes a lot of sense.
  22. I'm sure it's something to do with homeostasis. Homeostasis is essential for life. And again, why? LOL
  23. Yes, thank you. It is. Every time I look at this thread I look without looking, if you know what I mean. a = const. + sin(a) is a transcendental equation. Doh!!
  24. That's a good one. Phospholipids is another key. You need a barrier. I'd say it's the first thing you need before anything happens. Whatever proto-life was --pre DNA-RNA-proteo cycle-- it must happen in some kind of bubble. This view is part of standard wisdom too, if I'm not mistaken.
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