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Consistent effective description of nucleonic resonances in an unitary relativistic field-theoretic way

F. Kleefeld
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Abstract

High energy strong interaction physics is successfully described by the local renormalizable gauge theory called Quantum-Chromo-Dynamics (QCD) with quarks and gluons as ``elementary'' degrees of freedom, while intermediate energy strong interaction physics shows up to be determined by a non-local, non--renormalizable effective field theory (EFT) of ``effective'' degrees of freedom like mesons, ground state baryons and resonances. Within the picture of an effective field theory of strong interaction at intermediate energies I present a ``toy-model'' in which fermionic and bosonic resonances are considered to be ``particles'', i.e. they consistently are described by (anti-)commuting effective field-operators (containing dynamics of infinitely many quark-gluon or meson-nucleon diagrams) which are comfortably treated by Wick's Theorem in a covariant framework and obey unitarity. Non-trivial implications to couplings of non-local interactions are shown.

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F. Kleefeld. 1998-11-10. Consistent effective description of nucleonic resonances in an unitary relativistic field-theoretic way. https://arxiv.org/abs/nucl-th/9811032

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