# Tag Info

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Yes! The electron definitely doesn't have to be fundamental. In fact the LHC does searches that rule out electron compositeness up to a certain energy scale. If you're trying to make up the electron out of Standard Model (SM) quarks, you are going to run into problems: Why is the electron being bound together at such a higher scale than the typical strong ...

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At about 1 fm separation the strong force will resist the separation of the quark-antiquark pair any further and create a new quark-antiquark pair between the two. Now you have 2 quark-antiquark pairs using on quark from the newly created pair on each one, shortening the separation once more. This is a pretty good link of more or less exactly your question. ...

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You can determine this by using the vertices of the Standard Model (below) and building a Feynman diagram out of these vertices. The interaction $\rm e^+e^-\to e^+e^-$, known as Bhabha scattering, has interfering diagrams in both the s- and t-channels. In the s-channel, the two particles annihilate into a photon that then turns back into an electron and a ...

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The good reference is a book by https://www.amazon.com/Symmetries-Lie-Algebras-Represen-Mathematical/dp/0521541190 - it is a about group theory and application in Physics, but aimed more at mathematicians. I would also recommend https://www.amazon.com/dp/0521558859 as a something more applied and physicist aimed, with applications in crystallography and ...

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Any good QFT book would spend lots of space on vector-like (~nonchiral) interactions such as QED & QCD, and then contrast them to chiral ones for the weak interactions. I gather you are cool with the WP sample calculation. The basic vertices are equal mixtures of both chiralities,  eA_\mu \overline \psi \gamma^\mu \psi = e A_\mu \overline \psi _R \...

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Electrons and the quarks are fundamental in that (as far as we know) they are not comprised of other particles. And you cannot form an electron from three down quarks (even though the total charge will be -1) because even one down quark is much more massive than an electron. And all protons are comprised of 2 up and 1 down quark meaning they all have the ...

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1. Why, when $W^+$ or $W^-$ bosons are involved, sometimes the sign + or - is shown and sometimes not? The problem is that an X particle going from A to B is the same as an anti-X going from B to A, so there's ambiguity in whether any particular line ought to be labeled X or anti-X. The $W^+$ and $W^-$ are antiparticles of each other, so you could ...

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One possibility is that an electron and an anti-down quark simply scatter off each other. Another possibility is that the electron turns into an electron neutrino and the anti-down quark turns into an anti-up quark. With lower probability, other processes are possible in which more than two particles emerge. They don’t annihilate because they aren’t ...

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