Llosa, Josep2013-10-112013-10-112013-07-170022-2488https://hdl.handle.net/2445/46867The infinitesimal transformations that leave invariant a two-covariant symmetric tensor are studied. The interest of these symmetry transformations lays in the fact that this class of tensors includes the energy-momentum and Ricci tensors. We find that in most cases the class of infinitesimal generators of these transformations is a finite dimensional Lie algebra, but in some cases exhibiting a higher degree of degeneracy, this class is infinite dimensional and may fail to be a Lie algebra. As an application, we study the Ricci collineations of a type B warped spacetime.14 p.application/pdfeng(c) American Institute of Physics , 2013Àlgebra tensorialRelativitat general (Física)Simetria (Física)Física matemàticaÀlgebres de LieTensor algebraGeneral relativity (Physics)Symmetry (Physics)Mathematical physicsLie algebrasinfo:eu-repo/semantics/article6276432013-10-11info:eu-repo/semantics/openAccess