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A Mean Field Approximation to the Worldsheet Model of Planar phi^3 Field Theory

Korkut Bardakci·Charles B. Thorn
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Abstract

We develop an approximation scheme for our worldsheet model of the sum of planar diagrams based on mean field theory. At finite coupling the mean field equations show a weak coupling solution that resembles the perturbative diagrams and a strong coupling solution that seems to represent a tensionless soup of field quanta. With a certain amount of fine-tuning, we find a solution of the mean field equations that seems to support string formation.

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Korkut Bardakci, Charles B. Thorn. 2002-07-08. A Mean Field Approximation to the Worldsheet Model of Planar phi^3 Field Theory. https://doi.org/10.1016/s0550-3213(03)00004-x

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