Ontological Reinterpretation of the Physical Vacuum: From Mechanical Aether to a Pre-Stressed Elastic Continuum

This paper presents a unified ontological reinterpretation of fundamental space in modern physics. The null result of the Michelson- Morley experiment (1887) has historically been conflated with proof of the non-existence of any transmission medium, compelling theoretical physics to introduce abstract entities devoid of physical grounding. Applying Occam’s razor, we demonstrate that the vacuum behaves as an omnipresent, fully occupied, and elastically pre-stressed continuum. Electromagnetic excitations (photons) and gravitational perturbations are not autonomous ballistic projectiles traveling across nothingness, but quantized elastic stress impulses propagating at the characteristic phase velocity of the substrate, c (analogous to pressure shockwaves in pressurized hydraulics or electromagnetic signal transmission along conductors). The double-slit paradox is demystified: the introduction of a detector does not collapse a wave function via an observer's consciousness, but locally deforms the elastic impedance and phase coherence of the continuum itself. Furthermore, matter stability is shown to be maintained by an external omnidirectional compressive stress (press-on effect), directly substantiated by the Casimir effect, Meitner's anomalous gamma scattering, and the Schwinger limit. Finally, three falsifiable experimental challenges are formulated for the scientific community.