[Richard777 (OP)]

Four types of potential may be associated with a corresponding field.
The four potentials are;
Gravitational potential (Vm)   associated with a gravitational field
Electric potential (VQ)       associated with an electric field
Combined potential (VU)    associated with a “matter” field
Magnetic potential (VB)       associated with a magnetic field

Two “fundamental” potentials (VmS , VQS) include fundamental distances (rS , rQ).
Where;
rS is the Schwarzschild radius for mass
rQ is the electric length scale

Potential energies may be used to determine the binary interaction of massive or charged objects, and the field potential of a gravitational field, an electric field, or a magnetic field.
Reference attached