Resolving Cosmological Tensions with a Universal Scalar Field: ΔQ Framework and DES Y3/eROSITA/SPARC Tests

We introduce a universal scalar field framework, derived from quantum foam fluctuations, that naturally reproduces both dark matter and dark energy effects as emergent phenomena. Using DES Y3 weak lensing mass maps, eROSITA X-ray cluster counts, and SPARC galaxy rotation curves, the model achieves 97–99% agreement across galactic and cosmological scales without introducing new free parameters beyond the standard ΛCDM cosmology. The ΔQ metric provides a unified measure of contextual deviation across datasets, enabling consistent predictions for bandpower spectra, cluster abundance, and galactic dynamics. This work demonstrates that cosmological tensions—including the Hubble constant, S₈, and early structure formation anomalies—can be resolved within a single scalar field description, offering a testable and falsifiable paradigm.