%0 Journal Article %T The signature in actions of semisimple Lie groups on pseudo-Riemannian manifolds %A Rosales-Ortega %A Jos¨¦ %J Proyecciones (Antofagasta) %D 2012 %I Universidad Cat¨®lica del Norte %R 10.4067/S0716-09172012000100006 %X we study the relationship between the signature of a semisimple lie group and a pseudoriemannian manifold on wich the group acts topologically transitively and isometrically. we also provide a description of the bi-invariant pseudo-riemannian metrics on a semisimple lie group over r in terms of the complexification of the lie algebra associated to the group, and then we utilize it to prove a remark of gromov. %K semisimple lie groups %K bi-invariant metric %K local freeness . %U http://www.scielo.cl/scielo.php?script=sci_abstract&pid=S0716-09172012000100006&lng=en&nrm=iso&tlng=en