[Richard777 (OP)]

If so, this would relate quantum stuff to the EFE, little stuff to big stuff.
A gravitational wave function may provide such a link.
If the function interacts with a suitable energy operator, the result will be the Schroedinger equation.
A “wave equation”, may be related to the square of the wave-function.
The wave equation may simply transform to the Schwarzschild metric using two spatial frames.
(Reference; 14 Schroedinger)
Is such a link possible?

[PmbPhy]

If so, this would relate quantum stuff to the EFE, little stuff to big stuff.
A gravitational wave function may provide such a link.
If the function interacts with a suitable energy operator, the result will be the Schroedinger equation.
A “wave equation”, may be related to the square of the wave-function.
The wave equation may simply transform to the Schwarzschild metric using two spatial frames.
(Reference; 14 Schroedinger)
Is such a link possible?

That's a very vague question since the term can be taken to mean almost anything one wishes to if one wants to force a point.

However I'm confident to simply say No. First off the Schrodinger equation belongs to quantum mechanics while the Schwarzschild metric belongs to classical mechanics. The solution to the Schrodinger equation is a wave function while the Schwarzschild metric is a spacetime metric which represents the spacetime interval between two events which have a differential displacement in spacetime. There's no relationship between the two.

[Richard777 (OP)]

Would a "gravitational wave function" do the trick?

[jeffreyH]

The gravitational wave would disturb all other quantum phenomena. How on earth would you then unite them?