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arXiv · 1011.1850

Projecting the Bethe-Salpeter Equation onto the Light-Front and back: A Short Review

Tobias Frederico·Giovanni Salme`
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Abstract

The technique of projecting the four-dimensional two-body Bethe-Salpeter equation onto the three-dimensional Light-Front hypersurface, combined with the quasi-potential approach, is briefly illustrated, by placing a particular emphasis on the relation between the projection method and the effective dynamics of the valence component of the Light-Front wave function. Some details on how to construct the Fock expansion of both i) the Light-Front effective interaction and ii) the electromagnetic current operator, satisfying the proper Ward-Takahashi identity, will be presented, addressing the relevance of the Fock content in the operators living onto the Light-Front hypersurface. Finally, the generalization of the formalism to the three-particle case will be outlined.

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Tobias Frederico, Giovanni Salme`. 2010-11-08. Projecting the Bethe-Salpeter Equation onto the Light-Front and back: A Short Review. https://doi.org/10.1007/s00601-010-0163-z

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