Abstract
The Quantum Vacuum Universe (QVU) framework is proposed, in which an intrinsic vacuum stiffness, characterized by a universal acceleration scale aQV, links microphysics and cosmology. From this scale arises a “constants triangle” connecting the gravitational constant G, the cosmological constant Λ, and the vacuum stiffness parameter itself. This relation provides a microphysics-to-cosmos bridge with testable implications across galactic rotation curves, wide binaries, lensing, and cosmic acceleration. The framework is compatible with current astronomical data and offers clear pathways for falsification and refinement. Beyond cosmology, QVU also suggests novel interpretive connections to quantum foundations— including the double-slit experiment and entanglement—while remaining fully consistent with established quantum mechanical predictions.