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arXiv · hep-th/9507001

Instability of Solitons in imaginary coupling affine Toda Field Theory

S. Pratik Khastgir·Ryu Sasaki
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Abstract

Affine Toda field theory with a pure imaginary coupling constant is a non-hermitian theory. Therefore the solutions of the equation of motion are complex. However, in $1+1$ dimensions it has many soliton solutions with remarkable properties, such as real total energy/momentum and mass. Several authors calculated quantum mass corrections of the solitons by claiming these solitons are stable. We show that there exists a large class of classical solutions which develops singularity after a finite lapse of time. Stability claims, in earlier literature, were made ignoring these solutions. Therefore we believe that a formulation of quantum theory on a firmer basis is necessary in general and for the quantum mass corrections of solitons, in particular.

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S. Pratik Khastgir, Ryu Sasaki. 1995-07-03. Instability of Solitons in imaginary coupling affine Toda Field Theory. https://doi.org/10.1143/ptp.95.485

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