Bullough-Dodd model

The Bullough–Dodd model is an integrable model in 1+1-dimensional quantum field theory introduced by Robin Bullough and Roger Dodd. Its Lagrangian density is

where ${\displaystyle m_{0}\,}$ is a mass parameter, ${\displaystyle g\,}$ is the coupling constant and ${\displaystyle \phi \,}$ is a real scalar field.

The Bullough–Dodd model belongs to the class of Affine Toda Field Theories.

The spectrum of the model consists of a single massive particle.

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