Llosa, Josep2009-10-062009-10-0620031050-2947https://hdl.handle.net/2445/9566The paper by Woodward [Phys. Rev. A 62, 052105 (2000)] claimed to have proved that Lagrangian theories with a nonlocality of finite extent are necessarily unstable. In this Comment we propose that this conclusion is false.6 p.application/pdfeng(c) The American Physical Society, 2003Teoria quànticaTeoria de camps (Física)Equacions de LagrangeQuantum theoryField theoryLagrange equationsinfo:eu-repo/semantics/article504922info:eu-repo/semantics/openAccess