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arXiv · hep-th/9901110

Comparison of quantum field perturbation theory for the light front with the theory in lorentz coordinates

S. A. Paston·V. A. Franke
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Abstract

The relationship between the perturbation theory in light-front coordinates and Lorentz-covariant perturbation theory is investigated. A method for finding the difference between separate terms of the corresponding series without their explicit evaluation is proposed. A procedure of constructing additional counter-terms to the canonical Hamiltonian that compensate this difference at any finite order is proposed. For the Yukawa model, the light-front Hamiltonian with all of these counter-terms is obtained in a closed form. Possible application of this approach to gauge theories is discussed.

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S. A. Paston, V. A. Franke. 1999-01-22. Comparison of quantum field perturbation theory for the light front with the theory in lorentz coordinates. https://doi.org/10.1007/bf02583044

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