Causal Order as a Synchronic Determination of Holistic Physical Structures: Beyond One-Way Temporal Causality

Traditional physics and classical intuition rely heavily on the concept of unilateral, linear causality, in which causes strictly precede their effects in time. However, deep conceptual challenges arising from quantum mechanics, general relativity, and modern theories of quantum gravity indicate severe limitations of this one-way temporal causal chain at the fundamental level. This paper proposes an alternative physical paradigm: causality is not a localized process evolving unidirectionally along a fixed time axis, but rather a synchronic network jointly determined by the holistic physical structure, global boundary conditions, and topological-geometric features of the system. By analyzing delayed-choice experiments, quantum entanglement, action principles in classical and quantum field theories, and closed timelike curves in general relativity, we formulate a mathematical framework for "holistic structural causality" that operates independently of a unidirectional arrow of time. This framework demonstrates that the forward flow of time is merely an emergent thermodynamic property at the macroscopic scale. At the fundamental level, global phase-space constraints dictate the co-existence and mutual relations of events. This paradigm offers new perspectives for resolving the quantum measurement problem and the time-symmetry paradox, while unlocking valuable theoretical potential for modern cosmology and quantum gravity.