Abstract
In this paper, we study rank-1 projector solutions to the completely integrable Euclidean CPN−1 sigma model in two dimension and their associated surfaces immersed in the su(N) Lie algebra. We reinterpret and generalize the proof of A.M. Din and W.J. Zakzrewski [1980] that any solution for the CPN−1sigmamodeldefinedontheRiemannspherewithfiniteactioncanbewrittenasaraisingoperatoractingonaholomorphicone,oraloweringoperatoractingonaantiholomorphicone.Ourproofisformulatedintermsofrank−1Hermitianprojectorssoitisexplicitlygaugeinvariantandgivesnewresultsonthestructureofthecorrespondingsequenceofrank−1projectors.Next,weanalyzesurfacesassociatedwiththeCP^{N-1}modelsdefinedusingtheGeneralizedWeierstrassFormulaforimmersion,introducedbyB.Konopelchenko[1996].WeshowthatthesurfacesareconformallyparameterizedbytheLagrangiandensitywithfiniteareaequaltotheactionofthemodelandexpressseveralothergeometricalcharacteristicsofthesurfaceintermsoftheLagrangiandensityandtopologicalchargedensityofthemodel.Wedemonstratethatanysuchsurfacemustbeorthogonaltothesequenceofprojectorsdefinedbyrepeatedapplicationoftheraisingandloweringoperators.Finally,weprovidenecessaryandsufficientconditionsthatasurfaceberelatedtoaCP^{N-1}$ sigma model.