From D₈⁵ Symmetric Vacuum Geometry to Gravity as Return Dynamics: A Research Program

General relativity successfully describes gravity as spacetime curvature, but fails to answer fundamental questions such as the origin of matter and the underlying cause of spacetime bending. This paper proposes an exploratory research program: the ultimate spacetime of the universe is assumed to be an 11-dimensional manifold, with the vacuum ground state possessing D₈⁵ D₈ D₈ D₈ D₈ D₈ discrete symmetry. The 10-dimensional space is decomposed into five mutually independent two-dimensional subspaces, each acted upon by the dihedral group D₈ of order 16. Matter is interpreted as topological defect excitations formed by symmetry breaking in the high-dimensional vacuum geometry, while gravity is the intrinsic dynamical process of topological defects spontaneously returning to the symmetric vacuum ground state. This paper strictly distinguishes between geometric flow parameter and physical time, correcting logical confusions present in earlier drafts. The framework provides a unified explanation for long-standing physical puzzles including the hierarchy problem of gravity, the "fast-slow-fast" expansion history of the universe, the macroscopic arrow of time, and the common origin of fundamental interactions. In the low-energy compactification limit, this framework naturally yields field equations compatible with Memorial Gravity (TMG), inheriting its conclusion that galactic rotation curves can be fitted without dark matter. This paper presents multiple testable predictions: high-energy colliders can detect particle multiplets corresponding to the D₈⁵ group; spacetime discreteness and weak Lorentz violation exist at the Planck scale; gravitational waves exhibit scalar and vector polarization components beyond the standard tensor mode; and the dark energy equation of state evolves dynamically with redshift. The entire program is grounded in mainstream theoretical tools including string theory, orbifold compactification, and topological field theory, possesses falsifiability, and offers new perspectives for quantum gravity and unified field theory.