Accioly, A.Dias, M.2014-05-202014-05-202004-04-10Modern Physics Letters A. Singapore: World Scientific Publ Co Pte Ltd, v. 19, n. 11, p. 817-826, 2004.0217-7323http://hdl.handle.net/11449/23688Massive gravity models in (2 + 1) dimensions, such as those obtained by adding to Einstein's gravity the usual Fierz-Pauli, or the more complicated Ricci scalar squared (R-2), terms, are tree level unitary. Interesting enough these seemingly harmless systems have their unitarity spoiled when they are augmented by a Chern-Simons term. Furthermore, if the massive topological term is added to R + R-munu(2) gravity, or to R + R-munu(2), + R-2 gravity (higher-derivative gravity), which are nonunitary at the tree level, the resulting models remain nonunitary. Therefore, unlike the common belief, as well as the claims in the literature, the coexistence between three-dimensional massive gravity models and massive topological terms is conflicting.817-826engmassive gravity modelstopological termstree unitarityArtigo10.1142/S0217732304013362WOS:000221066800004Acesso restrito