- #1
orricl
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If susy really exist in nature, why does it not exist between leptons or quarks and gauge bosons such as photons, weak currents or gluons in the standard model?
SUSY Leptons & Quarks: Exploring Their Existence in Nature
In summary, the OP asked why there are no susy particles between the leptons and quarks in the standard model, and it appears that the answer is that supersymmetry provides a way to automatically balance out the forces between those particles.
- #2
mfb
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What do you mean with "between leptons or quarks and gauge bosons"? That does not make sense.
Supersymmetry (if it exists) gives every particle a corresponding partner (a bit more in the Higgs sector). We know that all known particles are not supersymmetric partners of other known particles.
Supersymmetry (if it exists) gives every particle a corresponding partner (a bit more in the Higgs sector). We know that all known particles are not supersymmetric partners of other known particles.
- #3
arivero
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mfb said:
This is a twist of the English language I am never sure of: Does "a particle" mean "one particle", or "at least one"? Because of each Weyl fermion we get two scalars.
- #4
mfb
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I don't want to go into details how to count particles, as I don't think it helps here.
- #5
haushofer
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Because the supersymmetry forces you to consider multiplets with particles which differ by (steps of) spin 1/2.
- #6
arivero
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Reading again the OP question, I think it asks for R-parity.
- #7
haushofer
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Ah, ok. I would say that these fermionic superpartners of the gauge bosons must sit in the same rep. of the gauge group, namely the adjoint. This is because gauge transfo's commute with susy. But quarks and leptons sit in the fundamental rep.
- #8
ChrisVer
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arivero said:
You have a good sense of imagination if you interpreted that question as a question on "R-parity"
...I think you can show that the susy algebra allows for an extension of U(1)-symmetry , whose generators follow certain algebra relations.
Also if I recall well, this extra symmetry can send some parameters in the Lagrangian to be very small to avoid e.g. proton decay with unreasonable lifetime...
Last edited:
- #9
Vanadium 50
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We've got 7 messages guessing what the OP meant. He's been back several times since he posted his question. Since he hasn't clarified it, I'd guess he no longer is interested in it, so all this arguing about what he means is probably futile.
- #10
ohwilleke
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Just for fun, I'll provide my reading of the OP:
I think the OP is asking, "why can't the Standard Model fundamental bosons be the superpartners of the Standard Model fundamental fermions?" The notion is that is supersymmetry is a symmetry between fundamental bosons and fundamental fermions. So, why don't the ones we have balance out without the need to hypothesize new sparticles to do the balancing.
The answer to that question is, that in SUSY the balancing is tautologically obvious which makes a variety of mathematical questions of broader concern in quantum physics much simpler. Any balancing between fermions and bosons in the Standard Model has cryptic origins that are not part of the Standard Model itself and are not understood at this time.
I think the OP is asking, "why can't the Standard Model fundamental bosons be the superpartners of the Standard Model fundamental fermions?" The notion is that is supersymmetry is a symmetry between fundamental bosons and fundamental fermions. So, why don't the ones we have balance out without the need to hypothesize new sparticles to do the balancing.
The answer to that question is, that in SUSY the balancing is tautologically obvious which makes a variety of mathematical questions of broader concern in quantum physics much simpler. Any balancing between fermions and bosons in the Standard Model has cryptic origins that are not part of the Standard Model itself and are not understood at this time.
1. What is SUSY and how does it relate to leptons and quarks?
SUSY (Supersymmetry) is a theoretical framework that proposes the existence of a partner particle for each known particle in the Standard Model of particle physics. This means that for every fermion (such as quarks and leptons), there would be a corresponding boson (such as Higgs boson and gauge bosons). SUSY predicts that these particles have the same properties except for their spin, thus providing a solution to some problems in the Standard Model and potentially explaining the existence of dark matter.
2. What evidence is there for the existence of SUSY leptons and quarks?
Currently, there is no direct evidence for the existence of SUSY particles. However, there are several pieces of indirect evidence that support the theory. For example, the measured mass of the Higgs boson aligns with the predicted mass in certain SUSY models, and the presence of dark matter in the universe can also be explained by SUSY particles. Additionally, the Large Hadron Collider (LHC) at CERN is actively searching for SUSY particles, and although no conclusive evidence has been found yet, the search continues.
3. How does the search for SUSY particles impact our understanding of the universe?
The search for SUSY particles is important because it has the potential to provide a more complete understanding of the fundamental building blocks of the universe. If SUSY particles are discovered, it would confirm the validity of the theory and open up new avenues for research and exploration. If they are not found, it would still provide valuable information about the limitations of the Standard Model and guide the development of new theories.
4. Are there any current experiments or projects focused on the search for SUSY particles?
Yes, there are several experiments and projects around the world that are dedicated to the search for SUSY particles. The most well-known is the Large Hadron Collider (LHC) at CERN, which collides particles at high energies to probe for the existence of SUSY particles. Other experiments include the Dark Energy Survey, the Super-Kamiokande neutrino detector, and the IceCube Neutrino Observatory, which all have the potential to provide evidence for SUSY particles.
5. How does the potential discovery of SUSY particles impact current scientific theories?
If SUSY particles are discovered, it would have a significant impact on our understanding of the universe and potentially revolutionize our current scientific theories. It would provide a solution to some of the problems in the Standard Model, such as the hierarchy problem and the existence of dark matter. It could also open up new areas of research and potentially lead to the development of a more comprehensive theory that unifies all known fundamental forces and particles.
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