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Duda Jarek

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  1. Sure, we can ask it using potential energy, e.g.: charged particle near atom behaves accordingly to superposition of Coulomb potential of electron being in all points, or maybe accordingly to single Coulomb potential: averaged over wavefunction?
  2. Electron has associated electric field, so asking about electric field of atom/orbital, is it superposition of electric field of electron being in each point, or maybe mean? For example placing another atom nearby, should their electrons somehow synchronize (e.g. van der Waals force)? Don't it require superposition?
  3. In other words: is electric field of orbital a superposition over electron being in all places, or rather mean?
  4. While electron and proton being far apart are allowed to be imagined as nearly point particles, when they approach ~10^-10m (or much more for Rydberg atoms), electron is said "to become" this relatively huge wavefunction - orbital, describing probability distribution of finding electron (confirmed experimentally e.g. https://journals.aps.org/prb/abstract/10.1103/PhysRevB.80.165404 ). Can we specify in what e-p distance this qualitative change happens? How to think about this orbital from QM interpretations perspective - is it superposition of electron (indivisible charge) being in all these places? E.g. in Many Worlds Interpretation, should we imagine that electron has different position in each World? In such superposition each electron is staying or moving? If staying, where e.g. the orbital angular momentum comes from? If moving, why no synchrotron radiation?
  5. Another very similar molecule is NH3 ... found e.g. on Pluto - not suggesting biological source only geological: https://advances.sciencemag.org/content/5/5/eaav5731 Detection of ammonia on Pluto’s surface in a region of geologically recent tectonism
  6. Oxygen-free environments seem characteristic for geological processes (?), and PH3 is similar to CH4 released by our geology - if phosphorus dominates instead of carbon, couldn't phosphine by synthesized in oxygen-free geological environments? "Geologic emissions of methane to the atmosphere": https://pubmed.ncbi.nlm.nih.gov/12430657/ ps. SH2 can be produced by bacteria: https://en.wikipedia.org/wiki/Hydrogen_sulfide#Biosynthesis_in_the_body Phosphine also occurs in Earth atmosphere ... and Jupiter: https://en.wikipedia.org/wiki/Phosphine#Occurrence Can be generated by bacteria: https://www.researchgate.net/publication/12507095_Phosphine_generation_by_mixed-_and_monoseptic-cultures_of_anaerobic_bacteria
  7. Here is their recent Lancet paper: https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)31866-3/fulltext https://www.reuters.com/article/us-health-coronavirus-russia-vaccine/russias-covid-19-vaccine-showed-antibody-response-in-initial-trials-idUSKBN25V1I2 Looks promising, but there are some suspicions: https://www.cnbc.com/2020/09/10/scientists-question-russian-vaccine-trial-data-on-unlikely-patterns.html Yesterday WHO vaccine report: https://www.who.int/publications/m/item/draft-landscape-of-covid-19-candidate-vaccines A worse news, probably the most promising (AstraZeneca) trial is on hold: https://www.nature.com/articles/d41586-020-02594-w
  8. It is also crucial that it is local random choice: based on possible single steps, having characteristic length like use of single step. MERW can be seen as scale-free limit of GRW_k: using uniform (/Boltzmann) distribution of length k paths from given position: GRW = GRW_1 MERW = lim_{k->infty} GRW_k
  9. Exactly, GRW is perfect e.g. for human wandering through the web, indeed performing local randomly looking decisions. MERW for electrons - having extremely complex EM&wave-based dynamics, expressing our limited knowledge through its entropy maximization, with Anderson-like localization property e.g. preventing semiconductor from being a conductor, like in below electron densities from STM (scanning tunneling microscope) from http://www.phy.bme.hu/~zarand/LokalizacioWeb/Yazdani.pdf The big question is what to choose between, like for this molecular dynamics? Practical difference is that only MERW has QM-like localization property - do we observe this kind of effects for molecules? Like entropic boundary avoidance, e.g. for [0,1] range GRW/diffusion/chaos would predict nearly uniform rho=1 stationary distribution, while QM/MERW predicts rho~sin^2 distribution avoiding boundaries - do we observe it for molecules?
  10. Thanks, my general thoughts is that: GRW should be used when the walker directly uses the assumed random walk, like "drunken sailor" throwing a dice in each node, or just human making looking random local decisions which link to click at for https://en.wikipedia.org/wiki/PageRank - it is for walkers performing nearly random decisions accordingly to local situation, having characteristic length like one web link. MERW stochastic propagator is nonlocal - depends on the entire space (in eigenequation of adjacency matrix) - it shouldn't be seen as directly used by the walker. Instead, this is thermodynamical picture - the safest (entropy maximizing) assumption we can make for limited knowledge situations like some complex hidden dynamics e.g. in electron conductance.
  11. To choose random walk on a graph, it seems natural to to assume that the walker jumps using each possible edge with the same probability (1/degree) - such GRW (generic random walk) maximizes entropy locally (for each step). Discretizing continuous space and taking infinitesimal limit we get various used diffusion models. However, looking at mean entropy production: averaged over stationary probability distribution of nodes, its maximization leads to usually a bit different MERW: https://en.wikipedia.org/wiki/Maximal_entropy_random_walk It brings a crucial question which philosophy should we choose for various applications - I would like to discuss. GRW - uses approximation of (Jaynes) https://en.wikipedia.org/wiki/Principle_of_maximum_entropy - has no localization property (nearly uniform stationary probability distribution), - has characteristic length of one step - this way e.g. depends on chosen discretization of a continuous system. MERW - is the one maximizing mean entropy, "most random among random walks", - has strong localization property - stationary probability distribution exactly as quantum ground state, - is limit of characteristic step to infinity - is discretization independent. Simulator of both for electron conductance: https://demonstrations.wolfram.com/ElectronConductanceModelsUsingMaximalEntropyRandomWalks/ Diagram with example of evolution and stationary denstity, also some formulas (MERW uses dominant eigenvalue):
  12. I have seen some papers that tritium is also found in volcanoes, suggest ongoing nuclear reactions (half-life ~12 years to to He3) https://www.sciencedirect.com/science/article/abs/pii/S0377027399001778 It brings interesting question of He3/He4 ratio in Earth mantle, e.g. http://www.mantleplumes.org/HeliumFundamentals.html Generally there is problem with He3 sources required for many application like ultra-cooling or lung imaging, especially after 911 as a lot of it was needed for neutron detectors for airport security. I have heard that its important source was decay of tritium in thermonuclear warheads and in some moment Russia has stopped selling ...
  13. Even deducing compression might be extremely tough, starting with question if it uses Huffman, arithmetic or ANS coding, for what probabilities ... deducing video compression from signal alone seems impossible task.
  14. Observational effects of strong magnetic fields are e.g. jets - are saying that their presence excludes possibility of black hole? I don't know - there are theoretized Kerr's black holes and I think they have magnetic field, also from acreting matter: https://en.wikipedia.org/wiki/Rotating_black_hole ? And the question is for the other side: imagine civilization without Einstein - developing low field corrections: succeeding terms of Taylor expansion of GR, not being aware that they should sum up to GR. Having QFT, they see renormalizability as crucial - how to convince them that non-renormalizable GR is the only way? For this purpose we need observational effect of black hole - convincing that it definitely isn't just a heavy neutron star, maybe using event horizon. Maybe Hawking radiation? How far are we from its direct observation?
  15. Without Einstein (situation this thread was supposed to be focused on) we would add corrections to Newton - first terms of Taylor expansion of GR ... mathematically getting agreement of low field effects. I have a feeling that you don't believe in Taylor expansion, Fermat principle ... here is this lecture again: And generally this is not discussion but bullying by moderators - not even trying to respond to arguments, only shooting some general remarks without any support. I am going to sleep now, would gladly discuss it tomorrow - but using argumentation instead ... low field is not enough, we need to go to high field like black hole - how exactly could such argument look like: to experimentally distinguish black hole from heavy neutron star?
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