Experimental Probes of the QGT:IR Framework Electrodynamic, Quantum, and Cosmological Tests of a Scalar-Structured Vacuum

The Quantum Gravity Theory based on Inverted Relativity (QGT:IR) is formulated as
a macroscopic effective field theory in which spacetime is assumed to be fundamentally
Minkowskian, while gravitational, cosmological, and thermodynamic phenomena emerge
from the collective response of a structured physical vacuum. The framework does not mod-
ify quantum electrodynamics, the Standard Model, or local general relativity, but introduces
a scalar modulation field governing effective vacuum response and universal open-system
dynamics.
In this work, we present a systematic experimental roadmap for probing the QGT:IR
framework across laboratory, quantum, and astrophysical regimes. We identify a set of
falsifiable and subdominant signatures, including cumulative spectral drift in electromagnetic
propagation, irreducible vacuum-induced noise, stability hierarchies governed by spectral
resonance, and the existence of universal decoherence floors in quantum systems. At larger
scales, we discuss possible subdominant spectral contributions to cosmological redshift and
the emergence of non-equilibrium stationary attractors in open thermodynamic systems.
We further extend the experimental program to the strong-response regime by considering
ultra-compact astrophysical objects, referred to as blackstars, which arise naturally within
QGT:IR as vacuum-stabilized, horizonless compact configurations. Although observationally
challenging, such objects may exhibit subtle deviations from ideal black hole behavior, includ-
ing imperfect absorption, late-time gravitational wave echoes, and non-thermal corrections
to Hawking-like emission. These signatures provide complementary, astrophysical probes of
vacuum structure without requiring modifications of established microscopic physics.
All proposed effects are explicitly formulated as effective, subdominant phenomena and
are accompanied by clear falsification criteria. The resulting experimental program estab-
lishes a controlled and testable interface between vacuum structure, open-system dynamics,
and emergent gravitational behavior, while remaining fully compatible with current empirical
constraints.