A Route toward Quantum Gravity through the Imaginary-Time Field Theory

A possible way toward the quantization of a weak gravitational field inspired by the imaginary-time field theory is discussed. The analogies of the general relativity in the canonical formulation with the thermodynamic geometry and superfluids are also pointed out. The proposed regularization method in the imaginary-time formalism of field theory shows a good chance removing theoretical obstacles and constructing a perturbative theory of quantum gravity.