Question

Criteria for being able to work with gravity in quantum mechanics, without a full theory of quantum gravity?

Answer 1

Quantum gravity (QG) is a field of theoretical physics that seeks to describe gravityaccording to the principles of quantum mechanics, and where quantum effects cannot be ignored,such as near compact astrophysical objects where the effects of gravity are strong.
There are a number of proposed quantum gravity theories.Currently, there is still no complete and consistent quantum theory of gravity, and the candidate models still need to overcome major formal and conceptual problems. They also face the common problem that, as yet, there is no way to put quantum gravity predictions to experimental tests, although there is hope for this to change as future data from cosmological observations and particle physics experiments becomes available