# QUANTUM THEORY OF GRAVITY. II. THE MANIFESTLY COVARIANT THEORY.

@article{Dewitt1967QUANTUMTO, title={QUANTUM THEORY OF GRAVITY. II. THE MANIFESTLY COVARIANT THEORY.}, author={Bryce S. Dewitt}, journal={Physical Review}, year={1967}, volume={162}, pages={1195-1239} }

Contrary to the situation which holds for the canonical theory described in the first paper of this series, there exists at present no tractable pure operator language on which to base a manifestly covariant quantum theory of gravity. One must construct the theory by analogy with conventional S-matrix theory, using the c-number language of Feynman amplitudes when nothing else is available. The present paper undertakes this construction. It begins at an elementary level with a treatment of the…

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