Massless finite and infinite spin representations of Poincaré group in six dimensions

Abstract: We study the massless irreducible representations of the Poincar\'{e} group in the six-dimensional Minkowski space. The Casimir operators are constructed and their eigenvalues are found. It is shown that the finite spin (helicity) representation is defined by two integer or half-integer numbers while the infinite spin representation is defined by the real parameter $\mu^2$ and one integer or half-integer number.