Equivalence of Covariant and Light-Front Perturbation Theory

N. C. J. Schoonderwoerd; B. L. G. Bakker

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arXiv · hep-ph/9610361

Equivalence of Covariant and Light-Front Perturbation Theory

N. C. J. Schoonderwoerd·B. L. G. Bakker

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Abstract

Light-Front Field Theory (LFFT) is a good candidate to describe bound states. In LFFT covariance is non-manifest. Burkardt and Langnau claim that, even for scattering amplitudes, rotational invariance is broken. We will take a different path of obtaining rules for light-front time-ordered diagrams. Covariance depends on the choice of a regulator $α$. We need to apply some regularisation scheme to render physical amplitudes finite. This is done by applying minus regularisation. In this process all ambiguities related to the regulator $α$ are removed. Therefore there is equivalence between the perturbative expansions of covariant and LFFT.

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N. C. J. Schoonderwoerd, B. L. G. Bakker. 1996-10-15. Equivalence of Covariant and Light-Front Perturbation Theory. https://arxiv.org/abs/hep-ph/9610361

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