"Performed or occurring as a result of a sudden inner impulse or inclination and without premeditation or
external stimulus."
"Can you name a process in physics that you think is spontaneous by your definition?"
Ultimately, the Aether is the source, supply, drain, sink,.. the medium required for all energy transfer to take place. All results from local "perturbations" of The Aether.
Only the existence of a field of force can account for the motions of the bodies as observed, and its assumption dispenses with space curvature. All literature on this subject is futile and destined to oblivion. So are all attempts to explain the workings of the universe without recognizing the existence of the ether and the indispensable function it plays in the phenomena. My second discovery was of a physical truth of the greatest importance. As I have searched the entire scientific records in more than a half dozen languages for a long time without finding the least anticipation, I consider myself the original discoverer of this truth, which can be expressed by the statement: There is no energy in matter other than that received from the environment. - Nikola Tesla
Magnetic Inductance is a polarized dimensional relation for the magnetic modalities of appearances (so to say) of the Ether, and Dielectric Capacitance is thus a non-dimensional inertial relation for the dielectric modalities of the Ether. For the magnetic induction the Ether modality is known as the magnetic permeability, for the dielectric induction the Ether modality is known as the dielectric permittivity. - Ken L. Wheeler
So, on one hand I can agree with the notion of The Sun being our most obvious local driver then immediately snatch that away and credit The Aether which is and always has driven everything we can experience or observe. However, on the other hand there's the concept of getting ridiculous. Of course, in modern physics parlance, two dissimilar metals in close proximity (a battery) noticeably producing a current can be considered "spontaneous." Phosphorescence as well for all practical purposes.