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joigus

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Everything posted by joigus

  1. This betrays a lack of understanding of what both coherence and entanglement actually mean. Please bear with me. Let us assume particles 1 and 2 are entangled in some way with respect to certain reference states \( \psi \) and \( \varphi \) of both identical-particle space of states. In your case, electrons. The state could be written without much loss of generality as, \[ \psi_{1}\varphi_{2}+\varphi_{1}\psi_{2} \] This can be phrased rather intuitively as "particle 1 could be in state \( \psi \) and particle 2 in state \( \varphi \), or particle 1 be in state \( \varphi \) and particle 2 in state \( \psi \). This is a typical situation of entanglement, and in a way it's akin to a superposition for particle 2 of states \( \varphi_{2} \) and \( \psi_{2} \), but in which the coefficients of the linear superposition, instead of complex numbers, are the (also complex) wave function components of particle 1, \( \psi_{1} \) and \( \varphi_{1} \). According to the formalism of quantum mechanics, the minutest interaction on particle 1 will introduce decoherence in the state as seen from the POV of particle 2, as \( \psi_{1} \) and \( \varphi_{1} \) of particle 1 will average over many mismatching phases, bringing about this lack of correlation between the complex coefficients accompanying \( \varphi_{2} \) and \( \psi_{2} \) that we know as decoherence. Therefore, entanglement guarantees decoherence as soon as interactions come into play, instead of precluding it, as you claim. In other words, you need to understand quantum mechanics.
  2. Not central to what we're discussing, but this is a flawed explanation of why electrons --or neutrons for that matter-- cannot have zero kinetic energy. Quantum particles cannot have zero kinetic energy due to Heisenberg's uncertainty principle, not to Pauli's exclusion principle. So any fermions must always have some kinetic energy in any given reference frame. Never mind other identical fermions being around. This is called ground-state kinetic energy or zero-point KE, and it's the least KE any particle can have. Were fermions allowed to have 0 KE because x,p were not complementary (HUP for position and momentum), they could still be at different places and still PEP would not be violated. What fermions cannot ever do is be in the same quantum state with however much kinetic energy HUP allows them to have. Glueballs aren't either. Yet nobody says glueballs are neutron stars just because they're not bunches of atoms. Things are not only defined by what they're not. Tritium isotopes are not "tiny neutron stars" either. Degeneracy pressure is not electrostatic repulsion, and gravitation has nothing to do with gluons and other ephimeral QCD states going back and forth between nucleons, which is what makes nucleons stick together by QCD. It's a very different animal. Neutron stars do not undergo fission via beta decay, as nucleons do. They do not have magic numbers. They do not have the same scattering properties, they don't have a definite spin statistics. Merging of neutron stars is nothing like nuclear fusion... And so on. \(\sim\)1057 neutrons packed together by gravity against Pauli's exclusion principle is what we call a neutron star \(\sim\)102 neutrons+protons packed together by QCD virtual states against electrostatic repulsion is what we call a nucleus The difference in name is justified because the phenomenology, what makes them, and most everything else, is different enough that it merits a different name.
  3. Nice! Yes I remember baboons depicted on a wall in Hatshepsut's tomb. But they're not the only ones, I think.
  4. Who said it?
  5. It's practiced nowhere, followed by no one, and you don't have to do anything to be a member. Doesn't have a point of view, knows not where he's going to isn't he a bit like you and me...?
  6. (n,101-n) would almost do the job you need. But you need the powers of ten to be "out of step" and catch up every two steps, so to speak. If you want a simple recipe the simplest one I can think of is with the floor function: floor(m)=floor(n+p/q)=n where n is the integer part of rational number m and p/q<1 is the rational part you need to add to n to get m. Then, (n,10-C(n)) where C(n) := floor((n-1)/2) https://en.wikipedia.org/wiki/Floor_and_ceiling_functions A good thing about floor is that you have it built in in Mathematica, Wolfram, and the like. You probably can do this with trigonometric functions too.
  7. Stability of a neutron star is due to balance between gravity and degeneracy pressure, rather than any kind of arrangement between QCD and QED, which is what gives stability to nuclei. Gravity, OTOH, plays no significant role in stability of nuclei. So a neutron star cannot be (sensibly) to be just a giant nucleus, IMO.
  8. Yeah, it rings a bell: https://www.scienceforums.net/search/?q="MHV"&quick=1
  9. And it's spilt over from there. Now it's about Netflix and the Bible.
  10. Reptilien? Is life German? You left out the most interesting bit of evolution, which is the transition from prokaryotes to eukaryotes. Once you have eukaryote life going, the combinatorics from reptilian to avian, or from reptilian to mammalian is rather trivial in comparison. I think. IOW, eukaryotic life only occured once for all we know. One swallow doesn't make a Summer.
  11. The quantum phenomenon responsible for quantum entanglement is quantum entanglement. Radiation, vacuum energy, and matter have very different equations of state with respect to the expansion parameter. I think I'm going with Mordred on this one.
  12. @Knowledge Enthusiast, for someone with the nickname of "knowledge enthusiast" you display very little enthusiasm in accepting hard-won knowledge from others. Ironic. http://www.scholarpedia.org/article/Complexity http://www.scholarpedia.org/article/Algorithmic_information_theory Oh, I almost forgot. Mass is not conserved. Energy is not conserved in cosmology either for the universe as a whole. It is true though that for a "small" object (eg, Mercury) falling in a static gravitational field, an analogue of Newtonian energy can be derived that is conserved. That is because a static gravitational field has a time-like Killing field and you can do that for that particular case. Actually, energy is quite a schizophrenic concept in general relativity, because the most you can do is to define 3 different energies. One of them is the matter-radiation energy on the right hand side of Einstein's equations. The other is some kind of "geometric energy" that people normally place on the LHS. Those two almost perfectly balance each other out, were it not for a 3rd --and weirdest of all-- kind of "energy" that we call vacuum energy. You need to learn some physics if you're going to talk about it. Put this in your pipe and smoke it: https://www.preposterousuniverse.com/blog/2010/02/22/energy-is-not-conserved/ As a university professor once said, "if you want to learn to write Chinese poetry, it seems like a good idea to start learning Chinese."
  13. You know what? I don't think anybody can answer that... The multiverse came from string theory, and nobody has ever been able to sensibly look into any of those patches of the landscape. My guess is that all that people do hardly goes beyond writing something called the partition function and trying to guess how many non-equivalent geometries there are (the famous Calabi-Yau manifolds). But I've read that the counting itself is incredibly challenging, let alone case studies of different geometries. @Mordred would probably tell you more and better. Provided he maintains his expert status.
  14. Not at all, "plauseable" is not a word. What is plausible, you think, the multiverse? I think the problem with the multiverse is how to make it a predictive idea. How to take it to the testing grounds of... well, the testing grounds.
  15. That was my original phrasing, There's your full stop. But It was ignored, so I dumbed it down.
  16. Exactly, because complexity has been defined, redefined, and refined in its definition, and studied for many decades now, so it's quite inane to try to define it all over again on one's own while ignoring decades and decades of study. And I mean the contemporary notion of it. I'm sure the Greeks thought about it too. Say what? Oh, yes, I must have forgotten to say: Mass is not conserved. Conserved in chemical reactions, not conserved in nuclear reactions. So not conserved. (nuclear or non-nuclear; any reactions involving number of particle change)
  17. Mass is not conserved.
  18. Sorry. I thought you'd lost interest. The point is that one can quite freely draw analogies, but that's all it is.
  19. Another interesting topological concept is that of closure.
  20. Lol. You reminded me of this true story: I once met a psychoanalyst with some background in physics that wanted to learn quantum mechanics. The money was good, so we arranged some tutoring hours every week and after we had the basics covered (limitations of classical electrodynamics, classical experiments and the like) I proceeded to teach him Fourier analysis, as he had studied multi-variable calculus and such, so it seemed appropriate, rather than the more abstract operator approach. Everything had gone quite smoothly thus far. But as soon as I said "every periodic function of a real variable can be expanded as a linear combination of sines and cosines of a fundamental frequency and successive harmonics blah blah" a glint of recognition appeared in his eyes. Now I must tell you the classes were in Spanish, and "sine" in Spanish translates as seno, which also means "bosom". Cosine (coseno) would be "co-bosom", I suppose. Anyway, he blurted something to the effect of "Oh, yes, I remember from psychoanalysis, the sine represents the female, while the cosine is the male". It was then and there that I knew the word Schrödinger would never be pronounced in those sessions.
  21. Why indeed? And why not indeed? As long as we're just drawing analogies, I think it's a valid one. And that's what you're doing. Is it not?
  22. What about the principle of least action, of which the speculations section offers so many examples? I think that should play a role in the standard model of the mind.
  23. Rotation speed of galaxies stars plotted against distance to galactic centre. It's explained in link provided by exchemist. Left-hand means "on the left side".
  24. Don't use Star Wars as your source for science, please. You might end up thinking you can hear explosions in outer space, or travel at superluminal speed. There's no reason I can think of that we cannot have Figrin D'an and the Modal Nodes some day. But don't hold your breath.
  25. A good place to start is trying to understand the virial theorem. Also, having a good understanding of physics beyond the standard model. The standard model is a pre-requisite for the latter. For starters, are you familiar with the fact that for gravitational systems the average kinetic energy is minus a half the average potential energy? If this thread goes well you could be on track to a Nobel Prize, who knows.
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