caa a22 4500 445385839 CHVBK 20180317143032.0 cr unu---uuuuu 170323e20110601xx s 000 0 eng 10.1007/s10714-011-1145-2 doi (NATIONALLICENCE)springer-10.1007/s10714-011-1145-2 Cotăescu Ion West University of Timişoara, V. Parvan Ave. 4, 300223, Timişoara, Romania aut The physical meaning of the de Sitter invariants [Elektronische Daten] [Ion Cotăescu] We study the Lie algebras of the covariant representations transforming the matter fields under the de Sitter isometries. We point out that the Casimir operators of these representations can be written in closed forms and we deduce how their eigenvalues depend on the field's rest energy and spin. For the scalar, vector and Dirac fields, which have well-defined field equations, we express these eigenvalues in terms of mass and spin obtaining thus the principal invariants of the theory of free fields on the de Sitter spacetime. We show that in the flat limit we recover the corresponding invariants of the Wigner irreducible representations of the Poincaré group. Springer Science+Business Media, LLC, 2011 de Sitter isometries nationallicence Covariant representations nationallicence Casimir operators nationallicence Unique spin nationallicence General Relativity and Gravitation Springer US; http://www.springer-ny.com 43/6(2011-06-01), 1639-1656 0001-7701 43:6<1639 2011 43 10714 https://doi.org/10.1007/s10714-011-1145-2 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10714-011-1145-2 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Cotăescu Ion West University of Timişoara, V. Parvan Ave. 4, 300223, Timişoara, Romania aut NATIONALLICENCE 773 0- General Relativity and Gravitation Springer US; http://www.springer-ny.com 43/6(2011-06-01), 1639-1656 0001-7701 43:6<1639 2011 43 10714 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer