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Optimized $δ$ expansion for the Walecka model

G. Krein·D. P. Menezes·M. B. Pinto
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Abstract

The optimized $δ$-expansion is used to study vacuum polarization effects in the Walecka model. The optimized $δ$-expansion is a nonperturbative approach for field theoretic models which combines the techniques of perturbation theory and the variational principle. Vacuum effects on self-energies and the energy density of nuclear matter are studied up to ${\cal O}(δ^2)$. When exchange diagrams are neglected, the traditional Relativistic Hartree Approximation (RHA) results are exactly reproduced and, using the same set of parameters that saturate nuclear matter in the RHA, a new stable, tightly bound state at high density is found.

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G. Krein, D. P. Menezes, M. B. Pinto. 1995-10-29. Optimized $δ$ expansion for the Walecka model. https://doi.org/10.1016/0370-2693(95)01578-7

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