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You state your age as 13, and it is not clear how much you know about elementary particles and interactions. This is the table of elementary particles in the standard model of physics And these are the forces with which the elementary particles interact and finally create matter as we see it everyday. The quarks within the proton and neutron interact ...


As in all extrapolations, one reaches a point where they break down. In the case of a black hole singularity and quark triplets ( neutrons and protons, pairs are quark antiquark i.e. mesons) falling into a black hole , the neutrons and protons falling in acquire energy from the gravitational energy of the black hole and at some point in energy will ...


The second one is a "quark diagram" or "quark model diagram". These are not 'true' Feynman diagrams, as they only represent the quark fields. The gluon field is implied, and it's an exercise for the reader to fill in the gaps. The only pedagogical source I can find is this: http://ned.ipac.caltech.edu/level5/Cottingham/Cott1_5.html (See the caption of ...


In your second diagram, there is implicitly a gauge boson source of your $q\bar{q}$ pair production. It could be a gluon, a photon or a $Z^0$. This gauge boson has to be attached to something, reasonably your single quark leg as in the first diagram.


Well, quark anti-quark pair can be created by a photon in a process like $$ \mu^- + \mu^+ \to \gamma \to q + \bar{q} \,,$$ which is just the time reversal of a typical Drell-Yan process, with the intermediate photon shown explicitly. Not sure if this really answers your question since you seem to be assuming a single quark initial state.


The transformation of a quark field under a group require you have to choose a representation of that group. It happen that the fundamental representation and the anti fundamental (bar) of $SU(N)$ with $N>2$ are inequivalent in the sense that there no non singular matrix independent of the representation chosen that allow us to make a change of basis and ...

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