The discussion revolves around the decay of elementary particles, particularly focusing on whether all elementary particles eventually decay into quarks, and the implications of proton decay in the context of stable nuclei and baryon number conservation. The scope includes theoretical considerations, speculative reasoning, and references to particle physics principles.
Participants express a range of views on the decay of elementary particles and the implications of proton decay. There is no consensus on whether proton decay is guaranteed or whether baryon number conservation is inviolable, indicating multiple competing perspectives remain unresolved.
Limitations in the discussion include unresolved assumptions about the nature of stable nuclei, the dependence on definitions of stability and decay, and the complexities surrounding baryon number conservation and its implications in the Standard Model.
zinq said:In case of heat death would it become a uniform quark soup?
Eventually proton decay should get rid of stable nuclei.mathman said:Why should stable nuclei decay at all?
Is that a given?Chalnoth said:Eventually proton decay should get rid of stable nuclei.
Most likely, yes. Proton decay is virtually guaranteed by simple symmetry arguments: some process created the protons, and the time reverse of that process would necessarily cause them to decay (note: it wouldn't quite be that simple, but that's the basic idea). The properties of that process may suppress it to an extremely low level (e.g. requiring a very massive intermediate particle, akin to how the masses of the weak force bosons suppresses the weak nuclear force), but simple arguments seem to indicate it's impossible to eliminate it entirely.256bits said:Is that a given?
I thought some experiments suggested the proton decay was virtually non-existent.
Comeback City said:is it not possible at all that certain "stable" nuclei have half-lives that are simply too long for us to determine?
Chalnoth said:Most likely, yes. Proton decay is virtually guaranteed by simple symmetry arguments: some process created the protons, and the time reverse of that process would necessarily cause them to decay (note: it wouldn't quite be that simple, but that's the basic idea). The properties of that process may suppress it to an extremely low level (e.g. requiring a very massive intermediate particle, akin to how the masses of the weak force bosons suppresses the weak nuclear force), but simple arguments seem to indicate it's impossible to eliminate it entirely.
They exist, and aren't balanced by anything in our universe with a negative baryon number. Look up baryogenesis if you want to see some of the current science surrounding this topic.snorkack said:What arguments are used to claim that any process ever created protons?
The difference is that proton decay is a microscopic reaction, while black holes and a "big crunch" are macroscopic.snorkack said:Simple symmetry arguments would suggest that time reversal of big bang would be big crunch, yet big crunch seems not to be expected now. Time reversal of a black hole is a white hole, yet white holes are also not expected.
Chronos said:The question of proton decay remains an open question in particle physics. One of the fundamental rules in particle physics is the total number of quarks minus the total number of antiquarks must not change in a decay.