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Winding number and non-BPS bound states of walls in nonlinear sigma models

Norisuke Sakai·Ryo Sugisaka
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Abstract

Non-supersymmetric multi-wall configurations are generically unstable. It is proposed that the stabilization in compact space can be achieved by introducing a winding number into the model. A BPS-like bound is studied for the energy of configuration with nonvanishing winding number. Winding number is implemented in an ${\cal N}=1$ supersymmetric nonlinear sigma model with two chiral scalar fields and a bound states of BPS and anti-BPS walls is found to exist in noncompact spaces. Even in compactified space $S^1$, this nontrivial bound state persists above a critical radius of the compact dimension.

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Norisuke Sakai, Ryo Sugisaka. 2002-05-13. Winding number and non-BPS bound states of walls in nonlinear sigma models. https://doi.org/10.1103/physrevd.66.045010

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