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arXiv · 1504.05502

Casimir operator dependences of non-perturbative fermionic QCD amplitudes

H. M. Fried·T. Grandou·R. Hofmann
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Abstract

In eikonal and quenched approximation, it is argued that the strong coupling fermionic QCD Green's functions and related amplitudes depart from a sole dependence on the SUc(3) quadratic Casimir operator, C2f, evaluated over the fundamental gauge group representation. Noticed in non-relativistic Quark Models and in a non-perturbative generalization of the Schwinger mechanism, an additional dependence on the cubic Casimir operator shows up, in contradistinction with perturbation theory and other non-perturbative approaches. However, it accounts for the full algebraic content of the rank-2 Lie algebra of SUc(3). Though numerically sub-leading effects, cubic Casimir dependences, here and elsewhere, appear to be a signature of the non-perturbative fermonic sector of QCD.

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H. M. Fried, T. Grandou, R. Hofmann. 2015-04-21. Casimir operator dependences of non-perturbative fermionic QCD amplitudes. https://doi.org/10.1142/s0217751x16501207

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