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Cross-ladder effects in Bethe-Salpeter and Light-Front equations

J. Carbonell·V. A. Karmanov
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Abstract

Bethe-Salpeter (BS) equation in Minkowski space for scalar particles is solved for a kernel given by a sum of ladder and cross-ladder exchanges. The solution of corresponding Light-Front (LF) equation, where we add the time-ordered stretched boxes, is also obtained. Cross-ladder contributions are found to be very large and attractive, whereas the influence of stretched boxes is negligible. Both approaches -- BS and LF -- give very close results.

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J. Carbonell, V. A. Karmanov. 2006-03-03. Cross-ladder effects in Bethe-Salpeter and Light-Front equations. https://doi.org/10.1140/epja%2Fi2005-10194-y

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