Singular charge endpoint of a complex sine-Gordon soliton
= Singular charge endpoint of a complex sine-Gordon soliton
{title2=$Q(0^\pm)=\pm2\pi/\lambda^2$}
At zero rotation the field reaches $\lambda^2|\psi|^2=1$ at its center. Its energy remains finite, but its charge expression is singular and has the two displayed one-sided limits. The regular local branch excludes this endpoint. A global completion must say whether and how these two limiting charge labels represent a physical state.