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nguyendung
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What is the full Lagrangian of Standard Model?How can we build a Lagrangian that satisfies both the symmetry SU(3) and the symmetry SU(2) at the same time?
Deep breath first! Then click here!nguyendung said:What is the full Lagrangian of Standard Model?
I'm not sure but I think they're referring to X and Y bosons. But hey...they're part of a GUT! and as far as I know, no GUT is part of SM yet!nguyendung said:What do X,Y stand for?
I know what you mean by that pain but I can agree about having that pain only when you're talking about someone who actually claims to know QFT and SM well. I never claimed such a thing. I just gave the OP a picture of the SM's Lagrangian and when he asked about X and Y, I said I'm not sure! So I see no reason for you to feel that pain!Vanadium 50 said:Second, it pains me to say that Shyan doesn't really know what he's talking about with the X and Y. These have nothing to do with GUTs. These are so-called "Popov Ghosts" and are an unnecessary complication at this level.
Shyan said:So either I'm wrong in the first sentence, or I'm wrong in the last sentence, or I'm wrong in thinking that picture shows the SM's Lagrangian.
From your first post, it is very clear that you have no knowledge about ordinary QFT let alone supersymmetric QFT. In order to benefit from PF, I suggest that you ask questions that match your level of understanding. Otherwise, you will be wasting your and other people time.nguyendung said:I have heard that almost SUGRA theories is not renormalizable(I am reading SUSY but not still SUGRA),then why do we still investigate SUGRA theories?
The full Lagrangian of the SU(3)xSU(2)xU(1) model is a mathematical expression that describes the fundamental interactions between particles in the theory. It includes terms for the strong, weak, and electromagnetic forces, as well as the interactions between particles and their corresponding fields.
The SU(3)xSU(2)xU(1) model is a specific version of the Standard Model of particle physics. It describes the fundamental particles and their interactions in terms of the symmetries of the SU(3)xSU(2)xU(1) group. The Standard Model also includes the Higgs mechanism, which gives particles their mass.
The SU(3) group represents the strong interaction in the SU(3)xSU(2)xU(1) model. It describes the interactions between quarks, which are the building blocks of protons and neutrons. The SU(3) symmetry gives rise to the eight gluons, which mediate these strong interactions.
The SU(2) group represents the weak interaction in the SU(3)xSU(2)xU(1) model. It describes the interactions between leptons, such as electrons, and the W and Z bosons. The U(1) group represents the electromagnetic interaction, describing the interactions between charged particles and the photon.
The SU(3)xSU(2)xU(1) model is a very successful theory in describing the fundamental particles and their interactions. It has been extensively tested and has made many accurate predictions. It also provides a framework for understanding the unification of the strong, weak, and electromagnetic forces, and has led to the development of other theories, such as supersymmetry, that attempt to unify all of the known forces in nature.