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Slow Blow Up in the (2+1)-dimensional S^2 Sigma Model

Jean Marie Linhart
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Abstract

We study singularity formation in spherically symmetric solitons of the charge one sector of the (2+1) dimensional S^2 sigma model, also known as $\IC P^1$ wave maps, in the adiabatic limit. These equations are non-integrable, and so studies are performed numerically on radially symmetric solutions using an iterative finite differencing scheme. Analytic estimates are made by using an effective Lagrangian cutoff outside a ball of fixed radius. We show the geodesic approximation is valid when the cutoff is applied, with the cutoff approaching infinity linearly as the reciprocal of the initial velocity. Additionally a characterization of the shape of a time slice f(r,T) with T fixed is provided.

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Jean Marie Linhart. 1999-09-12. Slow Blow Up in the (2+1)-dimensional S^2 Sigma Model. https://arxiv.org/abs/math-ph/9909014

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