"Unfortunately, the formulation of general rules for the calculation of in the quantum theory of gravitation has only confirmed the presence of another difficulty: The theory contains infinities, arising from integrals over large virtual momenta. Quantum electrodynamics contains similar infinities, but only in three or four special cases, where they can be dealt with by a renormalization of , , and wave functions. ... In contrast, the quantum theory of gravitation contains an infinite variety of infinities, as can be seen by an elementary dimensional argument: The gravitational constant has dimension ћ/m2, so a term in a dimensionless probability amplitude of order G'm will diverge like a integral ʃ p'2n–1'dp. In this respect, the theory of gravitation is more like other nonrenormizable theories, such as the of , than it is like quantum electrodynamics."