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billtodd
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Are there any GUTs where the proton never decays?
One should write such a theory, perhaps me...
One should write such a theory, perhaps me...
Are There GUTs Where the Proton Never Decays?
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In summary, the article explores the concept of Grand Unified Theories (GUTs) and examines scenarios in which protons may not decay. It discusses the implications of proton stability for GUTs, the potential for observable consequences in particle physics, and the significance of experimental results that suggest protons might have an extremely long lifespan. The piece highlights ongoing research and the importance of understanding the fundamental forces and particles in the universe while considering the implications for cosmology and the nature of matter.
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PeterDonis
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Where have you looked to find out?billtodd said:
That is off topic here, since PF is not for personal research.billtodd said:One should write such a theory, perhaps me...
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Vanadium 50
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He asked us!PeterDonis said:
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pinball1970
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you looked at this?billtodd said:Are there any GUTs where the proton never decays?
One should write such a theory, perhaps me...
https://link.aps.org/accepted/10.1103/PhysRevLett.119.241801
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berkeman
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(Thread prefix changed "A"-->"I")
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Vanadium 50
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It;s fairly trivial to do this. Protons decay via [itex]p \rightarrow e \mu \tau[/itex] and neutrons via [itex]n \rightarrow 3\nu[/itex]. The harder part is to make a model that does this "naturally".
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I looked at Wikipedia (German version) and got a brief, but sufficient answer. The English version is far more detailed so I didn't read it since I already had the main questions answered.Vanadium 50 said:
The question I would really like to be answered is: If it is true that Super-Kamiokande in Japan set a lower bound of ##1.6\cdot 10^{34}\,a## (by ##2017##), which are the consequences of this extremely marginal difference to stability. Admittedly, nearly zero and zero make a big difference in mathematics. But if I add the tolerance of measurement in the real world, can it ever be distinguished?
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Vanadium 50
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Are you worried about losing a sock to its protons decaying? Then you don't care if the lifetime has 34 or 36 zeroes. If you care which theory is right, then you do.
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Sure. I just wondered if they are distinguishable at all! Or in other words: are there other possible tests with higher expectations of success than starring at a huge tank and waiting forever? And if we detect something, can we be sure it wasn't just noise?Vanadium 50 said:
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Vanadium 50
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You can stare at a small tank for an even longer time. Most people don't consider this a step forward.
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PeterDonis
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Um, the difference between not observing anything that would indicate that a proton decay had happened, and observing such a thing? The former is what happened with Super Kamiokande. But if the latter had happened, it would have made a difference.fresh_42 said:
- #12
billtodd
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I know that neutron can decay (15 minutes in the limelight).Vanadium 50 said:
But I think that proton decay is impossible.
@PeterDonis you are right I haven't searched, I thought you knew of the existence of at least one theory that suggests an eternity lifetime for protons,,,,
- #13
billtodd
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In the abstract they write:"However, abandoning the requirement of absolute proton stability"pinball1970 said:
If there's no absolute stability shouldn't it decay eventually? That's not seems what I was looking for.
But thanks, I guess I really need to read my Group Theory books for physicists.
BTW does anyone know where may I find the report/article of Infinite Quantization by Mark Srednicki, was it ever published?
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PeterDonis
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Based on what?billtodd said:
Then you should. The answer to your question is easy to find, and I don't see why you should expect someone else to do that work for you.billtodd said:
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Vanadium 50
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Thank you for sharing your opinion.billtodd said:
The putative neutron decay [itex]n \rightarrow 3\nu[/itex] gets lumped in with "proton decay" as both processes violate baryon number conservation. The ordinary neutron decay [itex]n \rightarrow pe\nu[/itex] does not.
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billtodd
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Call it my GUT feeling...PeterDonis said:
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PeterDonis
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Personal speculation is off limits here.billtodd said:
Thread closed.
FAQ: Are There GUTs Where the Proton Never Decays?
1. What are Grand Unified Theories (GUTs)?
Grand Unified Theories (GUTs) are theoretical frameworks in particle physics that aim to unify the three fundamental forces of the Standard Model—electromagnetism, the weak nuclear force, and the strong nuclear force—into a single force. They propose that at high energy levels, these forces merge into one, and they often predict phenomena such as proton decay and the existence of new particles.
2. What is proton decay and why is it significant?
Proton decay is a hypothetical process predicted by many GUTs, where protons, which are generally considered stable in the Standard Model, would eventually decay into lighter particles over extremely long timescales. The significance of proton decay lies in its implications for the stability of matter and the understanding of fundamental forces, as its observation would support GUTs and provide insights into the early universe.
3. Are there GUTs that predict protons do not decay?
Yes, there are GUTs that propose scenarios where protons are stable and do not decay. These theories often involve different mechanisms or symmetries that prevent proton decay, suggesting alternative unification pathways or additional conservation laws. They challenge the conventional GUT framework and provide different perspectives on particle interactions.
4. What experimental evidence exists for or against proton decay?
As of now, no experimental evidence has conclusively demonstrated proton decay. Various experiments, such as Super-Kamiokande in Japan, have set lower bounds on the proton's lifetime, indicating that if it does decay, it occurs on a timescale longer than 10^34 years. This lack of evidence supports the stability of protons, but it does not rule out GUTs that predict proton decay.
5. How would the discovery of proton decay impact physics?
The discovery of proton decay would have profound implications for physics, as it would provide strong evidence for GUTs and suggest that our understanding of particle physics is incomplete. It would lead to new insights into the unification of forces, the nature of dark matter, and the evolution of the universe, potentially reshaping our understanding of fundamental particles and their interactions.