Eigenfunction Expansions Associated with the Second-Order Invariant Operator on Hyperboloids and Cones. III

Abstract
The eigenfunction expansions associated with the second‐order invariant operator on hyperboloids and cones are derived. The global unitary irreducible representations of the SO0(p, q) groups related to hyperboloids and cones are obtained. The decomposition of the quasi‐regular representations into the irreducible ones is given and the connection with the Mautner theorem and nuclear spectral theory is discussed.