from Hacker News

Are there individual protons and neutrons in a nucleus?

by firebaze on 9/24/24, 6:42 PM with 19 comments

  • by Jun8 on 9/24/24, 7:53 PM

    “By definition, all of the electrons in an atom are indistinguishable, which can arguably be rephrased to say that any electron in the electron cloud is the same electron as any other one.”

    For an even more mind boggling idea, see the one electron universe theory: https://news.ycombinator.com/item?id=40080266

  • by mncharity on 9/24/24, 9:36 PM

    > a single particle with mass and charge

    FWIW, atomic nuclei have fun substructure. They behave like inhomogeneous sometimes-oblate liquid drops[1] when large, and alpha-particle clusters[2] when small. I wonder if one could craft an introduction to atoms for kids, with rather more "you don't need this for the standardized exams, but here's a bunch of fun stuff you're usually not shown".

    [1] a plutonium fission model https://imgur.com/a/nlwzLyy [2] fig.4 on page 4 https://arxiv.org/pdf/1406.2473 Note wacky bowling-pin-shaped Neon.

  • by jjk166 on 9/24/24, 10:40 PM

    It's useful in the liquid drop model to think of the nucleus as being composed of a multitude of discrete particles. With each particle being an incompressible sphere, the strength of nuclear bonding makes sense as close nucleons interact strongly with eachother while more distant nuclei have weaker interactions, or beyond a certain point no interation, while their electromagnetic charges are not so hindered. It also scales up well for neutron stars, explaining why neutron star density matches nuclear density - in both cases it's just a bunch of piled up nucleons. Isomers make sense as different arrangements of the nucleons, and you can get some isomers with really funky geometries like halo nuclei.

  • by morelandjs on 9/24/24, 10:15 PM

    Physicists model heavy-ion collisions at the LHC using fluid dynamic simulations, and to get accurate predictions of final particle correlations, you need to account for the position fluctuations of discrete protons and neutrons within the nucleus.

  • by breck on 9/24/24, 8:03 PM

    When you are dealing with anything symbolic it's helpful to understand that all symbols are just concepts and measurements [0], and nothing else. You cannot really reduce the world to 2 dimensions. You need 4 for to describe reality, but then the map becomes the universe.

    [0] https://breckyunits.com/scrollsets.html

  • by fredgrott on 9/24/24, 8:00 PM

    to put it another way at the quantum level you are not looking at protons, electrons, neutrons, etc... until you attempt to measure one....

    Literally something is solid at our level due to how quantum objects behavior gets up to our macroscopic level.

    Or if you want to go further down the rabbit hole....Eastern dualism only is useful at the quantum level....not my words....someone else's.....start with Tao of Physics...yes it is reachable to non math people.