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This is great news, if it holds up. There hasn't been a lot of remarkable advancement in physics since the Standard Model. "Another topic that comes up is simp

This is great news, if it holds up. There hasn't been a lot of remarkable advancement in physics since the Standard Model. "Another topic that comes up is simplicity. According to Feynman, nature is usually much simpler than our thoughts. Therefore, when trying to explain phenomena, we tend to overcomplicate things. Often, in the end, reality can be explained by much simpler terms. We just need to look at it from another point of view." - https://cassandradispatch.org/richard-feynman-on-looking-at-the-world-from-another-point-of-view/ https://cassandradispatch.org/richard-feynman-on-looking-at-...

canjobear 3y ago
It doesn’t sound like this is necessarily a challenge to the Standard Model, only to one of the ways of approximately deriving predictions about the strong force.
cyberax 3y ago
The problem with the nucleus is that the internal dynamics there are impossible to describe with any reasonable precision. If for the electron shell we can calculate pretty much anything we want from the first principles (energy spectra, the half-lives of unstable and metastable states, etc.), we can't do anything similar for the nucleus. For example, we can't compute half-lives of unstable nuclear isotopes. The best models are on the level of "imagine that a nucleus is a drop of water" or "assume that a nucleus is a potential well that contains an alpha particle". And no, this is not a fundamental theory issue. We can describe the behavior of individual nuclear particles just fine at the energies that exist within the nucleus. It's their interaction that is completely baffling.
- jcranmer 3y ago
  > If for the electron shell we can calculate pretty much anything we want from the first principles (energy spectra, the half-lives of unstable and metastable states, etc.), we can't do anything similar for the nucleus. As I understand it, we can only really do that for a single-electron atoms. Multi-electron interactions get the same problem as inside the nucleus.
  - fsh 3y ago
    No, the problems are very different. The properties of multi-electron atoms can actually be calculated reasonably accurately with numerical methods, but including relativistic and quantum electrodynamic corrections is much harder than in single-electron systems. On the other hand, the coupling constant of the strong interaction is too large to permit perturbative calculations of bound systems. This makes calculations of nuclear properties fundamentally much more difficult, regardless of the particle number.
  - cyberax 3y ago
    > As I understand it, we can only really do that for a single-electron atoms. We can do it analytically for single-electron atoms. We can solve it numerically for much larger systems.
raverbashing 3y ago
For real, I wonder if Physicists are not putting themselves in a corner by using equations that are in principle "easy to work with" (because they're pulled from similar phenomenon) but a pain to actually use Feynman diagrams are a visual way of representing a boatload of very complex equations and the worse part is that they work! But maybe it's a failure of math more than physics

canjobear 3y ago

It doesn’t sound like this is necessarily a challenge to the Standard Model, only to one of the ways of approximately deriving predictions about the strong force.

cyberax 3y ago

The problem with the nucleus is that the internal dynamics there are impossible to describe with any reasonable precision. If for the electron shell we can calculate pretty much anything we want from the first principles (energy spectra, the half-lives of unstable and metastable states, etc.), we can't do anything similar for the nucleus. For example, we can't compute half-lives of unstable nuclear isotopes. The best models are on the level of "imagine that a nucleus is a drop of water" or "assume that a nucleus is a potential well that contains an alpha particle". And no, this is not a fundamental theory issue. We can describe the behavior of individual nuclear particles just fine at the energies that exist within the nucleus. It's their interaction that is completely baffling.

jcranmer 3y ago
> If for the electron shell we can calculate pretty much anything we want from the first principles (energy spectra, the half-lives of unstable and metastable states, etc.), we can't do anything similar for the nucleus. As I understand it, we can only really do that for a single-electron atoms. Multi-electron interactions get the same problem as inside the nucleus.
- fsh 3y ago
  No, the problems are very different. The properties of multi-electron atoms can actually be calculated reasonably accurately with numerical methods, but including relativistic and quantum electrodynamic corrections is much harder than in single-electron systems. On the other hand, the coupling constant of the strong interaction is too large to permit perturbative calculations of bound systems. This makes calculations of nuclear properties fundamentally much more difficult, regardless of the particle number.
- cyberax 3y ago
  > As I understand it, we can only really do that for a single-electron atoms. We can do it analytically for single-electron atoms. We can solve it numerically for much larger systems.

raverbashing 3y ago

For real, I wonder if Physicists are not putting themselves in a corner by using equations that are in principle "easy to work with" (because they're pulled from similar phenomenon) but a pain to actually use Feynman diagrams are a visual way of representing a boatload of very complex equations and the worse part is that they work! But maybe it's a failure of math more than physics