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Duda Jarek

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Posts posted by Duda Jarek

  1. 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?

  2. 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

  3. 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

    Quote

    In an open letter to the editor of the medical journal, 27 scientists said the data published was incomplete and had shown some “unlikely patterns.”

     

    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

  4. 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

    obraz.thumb.png.62a95349ccc25a68ce0aae54cbfee771.png

    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?

  5. 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.

    obraz.thumb.png.5e55a003a8f5025abcc69a627678a4fb.png

  6. 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):

    dcYlkvL.png

  7. 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

    Quote

    (...)we analyzed samples from 11 active volcanoes ranging in composition from tholeiitic basalt to rhyolite: Mount St. Helens (USA), Kilauea (USA), Pacaya (Guatemala), Galeras (Colombia), Satsuma Iwo-Jima (Japan), Sierra Negra and Alcedo (Ecuador), Vulcano (Italy), Parı́cutin (Mexico), Kudryavy (Russia), and White Island (New Zealand). Tritium at relatively low levels (0.1–5 T.U.) is found in most emissions from high-temperature volcanic fumaroles sampled(...)

    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 ...

  8. 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?

  9. 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:

    40 minutes ago, Duda Jarek said:

    just found some "Introduction to Gravitational Lensing Lecture scripts" http://www.ita.uni-heidelberg.de/~massimo/sub/Lectures/gl_all.pdf

    Quote

    1.2 Fermat’s principle and light deflection

    Starting from the field equations of general relativity, light deflection can be calculatedby studying geodesic curves. It turns out that light deflection can equivalently be described by Fermat’s principle, as in geometrical optics. This will be our starting point

     

    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?

  10. Are you claiming that light in gravitational lensing do not behave accordingly to Fermat's principle? Interesting, could you support it somehow?

    I don't know what do you mean by anti-GR preaching, but let me remind: this thread was supposed to be focused on argumentation to convince to GR (non-renormalizable, without Einstein).

    Once again, using low field arguments would not work as, without Einstein, there could be just developed succeeding terms of Taylor expansion of GR instead.

    We need strong field arguments like black hole - how they could be used to convince that a given object is not just a heavy neutron star?
     

    update: just found some "Introduction to Gravitational Lensing Lecture scripts" http://www.ita.uni-heidelberg.de/~massimo/sub/Lectures/gl_all.pdf

    Quote

    1.2 Fermat’s principle and light deflection

    Starting from the field equations of general relativity, light deflection can be calculatedby studying geodesic curves. It turns out that light deflection can equivalently be described by Fermat’s principle, as in geometrical optics. This will be our starting point

    Mathematics is the same, especially for all low field approximations as first Taylor terms.

  11. Wave propagation is usually governed by Fermat's principle (similar to the least action principle):

    Quote

    the path taken by a ray between two given points is the path that can be traversed in the least time

    leading for example to refraction due to slow down in some medium, allowing e.g. to build lenses - not necessarily using strong boundaries between materials, can be gradient like in gravitational case.

    GR uses intrinsic curvature instead, but in Fermat's principle it can be interpreted as slowing down in presence of gravitational field.

     

    Here is some related paper: https://journals.aps.org/prd/abstract/10.1103/PhysRevD.96.104037

    Gravitomagnetic bending angle of light with finite-distance corrections in stationary axisymmetric spacetimes

     

    Anyway, bending we observe is low field effect - can be obtained by replacing GR with first terms of its Taylor expansion.

    The big question is how to conclude non-renormalizable GR from them? I am afraid that convincing arguments might require strong field effects like black holes ...

  12. Searching for materials about Mercury precession, they usually refer to GEM, e.g.:

    https://www.worldscientific.com/doi/abs/10.1142/S2010194517600527

    Quote

    The Gravitomagnetism in the Solar System

    In 1918, Joseph Lense and Hans Thirring discovered the gravitomagnetic (GM) effect of Einstein field equations in weak field and slow motion approximation. They showed that Einstein equations in this approximation can be written as in the same form as Maxwell’s equation for electromagnetism. In these equations the charge and electric current are replaced by the mass density and the mass current. Thus, the gravitomagnetism formalism in astrophysical system is used with the mass assuming the role of the charge. In this work, we present the deduction of gravitoelectromagnetic equations and the analogue of the Lorentz force in the gravitomagnetism. We also discuss the problem of Mercury’s perihelion advance orbit, we propose solutions using GM formalism using a dipole-dipole potential for the Sun-Planet interaction.

    But Heavisides' 1893 GEM paper has only citation before 1950 (now 315):

    https://scholar.google.pl/scholar?hl=en&as_sdt=2005&sciodt=0%2C5&cites=5741552482440482063&scipsc=&as_ylo=1800&as_yhi=1950

    It looks like just nobody was aware of this paper back then (?)

     

    Update: from https://arxiv.org/pdf/gr-qc/0207065.pdf

    Quote

    In 1893 Oliver Heaviside[6] [7] investigated the analogy between gravitation and electromagnetism; inparticular, he explained the propagation of energy in a gravitational field, interms of a gravitoelectromagnetic Poynting vector, even though he (just asMaxwell did) considered the nature of gravitational energya mystery. Theformal analogy was then explored by Einstein [8], in the framework of GeneralRelativity, and then by Thirring [9] who pointed out that thegeodesic equationmay be written in terms of a Lorentz force, acted by a gravitoelectric andgravitomagnetic field.

     

  13. This is discussion forum, I have created general thread to discuss violation of baryon number - among others asking if it is possible, if so where it could be observed, how it could be verified.

    I don't know if it happens in neutron stars, I have never claimed it - this is only one of topics to discuss here, I am asking for arguments in both sides.

    Maybe indeed it should be neglected or "discarded in 30 seconds", but I don't know the argumentation behind it and would gladly learn.

  14. Baryon number violation is not my idea, but a phenomenon required e.g. for baryogenesis, Hawking radiation, supersymmetry, GUT, sphelatron and many others.

    I am not claiming anything, only asking, trying to discuss if it could also have other astronomical consequences, for example those which (as they claim) cannot be explained in standard way, like this https://www.space.com/35846-brightest-farthest-neutron-star-discovered.html

    "Astronomers have discovered the brightest neutron star ever found. This extremely dense object is 1,000 times brighter than researchers previously thought was possible for neutron stars (...) This is one of the questions the scientific community needs to answer in the next years "

  15. 1 minute ago, Strange said:

    Then why do you keep bringing up your false and off-topic claims about GEM.

    I am just referring to Wikipedia (e.g. copy&pasted table), which uses GEM all around for low field GR effects ... and don't see any "off topic claims" - please specify.

    4 minutes ago, Strange said:

    Space is not full of water.

    Bending wave is universal for propagation with different speeds - is not limited to water, or EM waves:

    https://en.wikipedia.org/wiki/Refraction

    https://en.wikipedia.org/wiki/Structural_acoustics

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