Welcome back ether?
https://en.wikipedia.org/wiki/Aether_theories
a space-filling substance or field, thought to be necessary as a transmission medium for the propagation of electromagnetic or gravitational forces.
There can only be one force, and a second mechanism acting on that force to give the appearance of 4 forces.
Reduce them to one, and then you are done.
The legendary "Flotus wood".
There can be only one, what is the cause of the variance?
The median can cause a distortion, or force is not fully applied in one dimension, IE Gravity, and why it is the key. If Gravity and the 3 other forces are but one force, where is the missing force IE weak nuclear, why would you have 2? if derived from the same source.
Force acting across dimensions, and giving the appearance of being weaker, would give consolidation to the 4 forces, and tell us UFO are not from out there, but over there.
or the rim of a black hole, your choice.