Brandt, FriedemannGomis Torné, JoaquimSimón, Joan2010-06-082010-06-0819980031-9007https://hdl.handle.net/2445/12798We show that the symmetries of effective D-string actions in constant dilaton backgrounds are directly related to homothetic motions of the background metric. In the presence of such motions, there are infinitely many nonlinearly realized rigid symmetries forming a loop (or looplike) algebra. Near horizon (antideSitter) D3 and D1+D5 backgrounds are discussed in detail and shown to provide 2D interacting field theories with infinite conformal symmetry.4 p.application/pdfeng(c) American Physical Society, 1998Teoria de camps (Física)Partícules (Física)General theory of fields and particlesinfo:eu-repo/semantics/article169340info:eu-repo/semantics/openAccess