Unified Theory of Spacetime Rhythm – A Relativistic Framework Based on Worldline Curvature Modulation Principle

The overall theoretical framework of the "Unified Theory of Spacetime Rhythm" was initially formulated several years ago. It not only points out a clear and operable optimization direction for the Cosmological Holographic Dynamics (CHD) Theory but also constructs an innovative bridge connecting classical gravity and quantum gravity. Far from subverting or negating the existing theoretical system, this theory expands and deepens on the basis of compatible with the core paradigm of general relativity——in the low-energy limit, it can strictly reduce to the form and predictions of general relativity, ensuring consistency with existing observational results; at the same time, by introducing a dynamic rhythm field and the curvature-rhythm correspondence principle, it provides a clear physical carrier and testable experimental signals for the low-energy observation of quantum gravity effects. This paper proposes a novel relativistic framework—the Unified Theory of Spacetime Rhythm—based on the principle of worldline curvature modulation, aiming to reconstruct the nature of time and resolve the core contradictions between classical gravitational theory and cosmological observations. The theory is founded on three core cognitions: time is an emergent phenomenon, spacetime possesses intrinsic geometry, and relativistic effects exhibit both geometric and physical duality. Through four basic postulates, a direct correlation between local time rhythm and worldline curvature is established, and a dynamic rhythm field Θ(x) is introduced to modulate the strength of gravitational coupling. The mathematical model of the theory is based on the principle of least action, constructing a coupled dynamic system of the metric field and the rhythm field, and deriving modified gravitational field equations and matter equations of motion. In the weak-field static spherically symmetric limit, the theory naturally reduces to general relativity while predicting testable new phenomena such as the Nordtvedt effect that violates the strong equivalence principle. Cosmological applications show that the energy-momentum of the rhythm field can act as dynamical dark energy, explaining cosmic accelerated expansion without introducing a finely tuned cosmological constant, and provides predictions with measurable differences from the ΛCDM model in terms of high-redshift Hubble parameters and the evolution of the dark energy equation of state. In addition, the theory is naturally compatible with inflation models and offers a new solution to the time problem in quantum gravity. With both logical self-consistency and observational falsifiability, this theory is a potential bridge connecting classical gravity and quantum gravity. AN HAIZHONG 496554365@qq.com