Noncommutative vortex solitons

We consider the noncommutative Abelian-Higgs theory and investigate general static vortex configurations including recently found exact multivortex solutions. In particular, we prove that the self-dual Bogomol'nyi-Prasad-Sommerfield (BPS) solutions cease to exist once the noncommutativity scale exceeds a critical value. We then study the fluctuation spectra about the static configuration and show that the exact non-BPS solutions are unstable below the critical value. We have identified the tachyonic degrees as well as massless moduli degrees. We then discuss the physical meaning of the moduli degrees and construct exact time-dependent vortex configurations where each vortex moves independently. We finally give the moduli description of the vortices and show that the matrix nature of moduli coordinates naturally emerges.