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Constructing Point Form Mass Operators from Interaction Lagrangians

W. H. Klink
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Abstract

Starting from an interaction Lagrangian formed out of local fields, an interacting four-momentum operator is constructed by integrating the interaction Lagrangian over the forward hyperboloid. Such a four-momentum operator has the property that the components commute among themselves; however, when the Fock space on which the four-momentum operator acts is truncated, the components no longer commute among themselves. By modifying matrix elements of the four-momentum operator on the truncated space, Bakamjian-Thomas mass operatorsare constructed which restore the Poincare relations. Examples for a simple Lagrangian are given.

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W. H. Klink. 2002-09-20. Constructing Point Form Mass Operators from Interaction Lagrangians. https://doi.org/10.1016/s0375-9474(02)01406-9

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