Minimal Algebras for Relativistic Wave Equations

The idea that matrices occuring in both first and second order relativistic wave equations generate (under commutation) some finite Lie algebra, which contains the Lorentz algebra, is considered. For first and second order wave equations the minimal non trivial Lie algebras are so(3,2) and sl(4,R) respectively. The unique mass condition and the so(3,2) algebra rule out all but the Dirac and Duffin-Kemmer equations, while the sl(4,R) algebra is associated to the Klein-Gordon, Proca and Joos-Weinberg (spin 1) equations

Spinors for Spinning p-Branes

The group of the p-brane world volume preserving diffeomorphism is considered. The infinite-dimensional spinors of this group are related, by the nonlinear realization techniques, to the corresponding spinors of its linear subgroup, that are constructed explicitly. An algebraic construction of the Virasoro and Neveu-Schwarz-Ramond algebras, based on this infinite-dimensional spinors and tensors, is demonstrated.Comment: 18 page

Generalization of the Gell-Mann formula for sl(5, R) and su(5) algebras

The so called Gell-Mann formula expresses the Lie algebra elements in terms of the corresponding Inonu-Wigner contracted ones. In the case of sl(n, R) and su(n) algebras contracted w.r.t. so(n) subalgebras, the Gell-Mann formula is generally not valid, and applies only in the cases of some algebra representations. A generalization of the Gell-Mann formula for sl(5,R) and su(5) algebras, that is valid for all representations, is obtained in a group manifold framework of the SO(5) and/or Spin(5) group

World Spinors - Construction and Some Applications

The existence of a topological double-covering for the $GL(n,R)$ and diffeomorphism groups is reviewed. These groups do not have finite-dimensional faithful representations. An explicit construction and the classification of all $\bar{SL}(n,R)$, $n=3,4$ unitary irreducible representations is presented. Infinite-component spinorial and tensorial $\bar{SL}(4,R)$ fields, "manifields", are introduced. Particle content of the ladder manifields, as given by the $\bar{SL}(3,R)$ "little" group is determined. The manifields are lifted to the corresponding world spinorial and tensorial manifields by making use of generalized infinite-component frame fields. World manifields transform w.r.t. corresponding $\bar{Diff}(4,R)$ representations, that are constructed explicitly.Comment: 19 pages, Te