On a Riemannian Method in Quantum Theory about Curved Space-time*)

We start from a given Lorentz metric and a vector field of world lines along which observers and measure devices may move. We describe a procedure to associate one-particle Hilbert spaces and one-particle Hamiltonians to space-like hypersurfaces using a transi, tion to a Riemannian metric. With the aid of suitable boundary conditions one can confine the particle within a world tube ("box quantization about curved space-time manifolds").