Abstract
The perturbation series of Dashen and Frautschi is derived via a "$D$-matrix" approach to all orders in the perturbation. Explicit formulas are given for the first and second orders, and their equivalence to the Rayleigh-Schr\"odinger perturbation series in potential theory is shown. A method is then given to carry out the evaluation of the series to any order. The first-order formula is examined in three models; the four-point interaction, two-particle scattering with a left-hand cut given by a single pole, and an augmented Lee model. The exact results of these models are shown to agree in each case with the theory of Dashen and Frautschi. Finally, we discuss differences between the Lee-model calculation presented here and Dashen's calculation of the neutron-proton mass difference.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
