Dynamic Spacetime Fluid Cosmology

This formal theoretical treatise introduces a novel cosmological framework that reconceptualizes spacetime not as a passive vacuum, but as a dynamic, energetic continuum termed the "spacetime fluid". Addressing the limitations of current cosmological paradigms—such as the elusive nature of dark matter, dark energy, and the unification of fundamental forces—the model posits that this fluid originates from and is sustained by a continuous thermodynamic energy influx from a higher-dimensional manifold. Within this framework, mass is redefined not as an intrinsic entity, but as a stable, localized topological excitation maintained by a volume-dependent absorption of the surrounding continuum's energy. The treatise posits that this continuous energy absorption creates localized, exponential depressions in the fluid's viscosity. Consequently, these mass-induced viscosity gradients formally dictate spacetime curvature, where superposed gradient fields—rather than classical pressure mechanics—drive the macroscopic phenomenon of gravitational attraction. Additionally, Version 2.0 formalizes this model by introducing a decoupled mathematical architecture. It replaces the classical metric tensor of General Relativity with a fluid-dynamic Viscosity Tensor, reinterprets inertia as thermodynamic gradient displacement, structures the fundamental interactions as a hierarchical system of gauge conversion modes, and calibrates the fluid breakdown against the quantum bounds of the Standard Model. By exploring the Cosmic Microwave Background as a dimensional boundary manifold and framing dark energy and dark matter as emergent fluid properties, this preprint establishes a rigorous mechanical foundation for relativistic phenomena.