One Theory Fits All—from the Very Distant to the Very Small

Special and general relativity (SR/GR) work for observers, but they do not provide diagrams of nature that work for all observers. This is because there is no concept of absolute space in SR/GR, where all action is due to an absolute parameter. We show: Euclidean relativity (ER) achieves precisely that. ER describes a mathematical Master Reality, which is absolute 4D Euclidean space (ES). All objects move through ES at the dimensionless speed C. There is no time coordinate in ES. All action in ES is due to an absolute, external evolution parameter θ. In addition, ER describes an observer’s physical reality. He experiences two projections of ES as space and time. The axis of his current 4D motion is his proper time τ. Three orthogonal axes make up his 3D space x₁, x₂, x₃. Without gravity, his physical reality is a Minkowskian reassembly of his axes x₁, x₂, x₃, τ. In this “τ-based Minkowskian spacetime” (τ-MS), τ is the time coordinate and θ converts to parameter time ϑ. Minkowski spacetime and τ-MS are mathematically identical. Thus, ER retains the SR formalism. ER also retains the GR formalism, but only in a specific reference frame defined by τ. The Einstein field equations hold true in this specific frame, but not in ES. ER reproduces both the Lorentz factor and gravitational time dilation. ER rejects cosmic inflation, expanding space, dark energy, and non-locality. And yet, ER predicts time’s arrow, galactic motion, the Hubble tension, and entanglement. Thus, ER significantly improves cosmology and quantum mechanics. We conclude: ER is indispensable for unifying physics.