The QCD vacuum and its hadronic excitations
نویسنده
چکیده
These lectures deal with the complex structure of the ground state, or vacuum, of Quantum Chromo Dynamics (QCD) and its low-energy excitations, the hadrons. QCD, the theory of quarks, gluons and their interactions, is a self-contained part of the Standard Model of elementary particles. It is a consistent quantum field theory with a simple and elegant underlying Lagrangian, based entirely on the invariance under a local gauge group, SU(3)color. Out of this Lagrangian emerges an enormously rich variety of physical phenomena, structures and phases. Exploring and understanding these phenomena is undoubtedly one of the most exciting challenges in modern science.
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