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arXiv · hep-th/0604219

Moduli-Space Dynamics of Noncommutative Abelian Sigma-Model Solitons

Michael Klawunn·Olaf Lechtenfeld·Stefan Petersen
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Abstract

In the noncommutative (Moyal) plane, we relate exact U(1) sigma-model solitons to generic scalar-field solitons for an infinitely stiff potential. The static k-lump moduli space C^k/S_k features a natural K"ahler metric induced from an embedding Grassmannian. The moduli-space dynamics is blind against adding a WZW-like term to the sigma-model action and thus also applies to the integrable U(1) Ward model. For the latter's two-soliton motion we compare the exact field configurations with their supposed moduli-space approximations. Surprisingly, the two do not match, which questions the adiabatic method for noncommutative solitons.

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Michael Klawunn, Olaf Lechtenfeld, Stefan Petersen. 2006-06-07. Moduli-Space Dynamics of Noncommutative Abelian Sigma-Model Solitons. https://doi.org/10.1088/1126-6708%2F2006%2F06%2F028

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