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Instantaneous Bethe-Salpeter equation: improved analytical solution

Wolfgang Lucha·F. F. Schoberl
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Abstract

Studying the Bethe-Salpeter formalism for interactions instantaneous in the rest frame of the bound states described, we show that, for bound-state constituents of arbitrary masses, the mass of the ground state of a given spin may be calculated almost entirely analytically with high accuracy, without the (numerical) diagonalization of the matrix representation obtained by expansion of the solutions over a suitable set of basis states.

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Wolfgang Lucha, F. F. Schoberl. 2001-09-19. Instantaneous Bethe-Salpeter equation: improved analytical solution. https://doi.org/10.1142/s0217751x0200976x

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