Quantum Evolution and Measurement in the Scalar Temporal Field Ontology

The Scalar Temporal Field Ontology (STFO) treats time as a physical scalar field whose spacetime gradients define causal ordering and temporal directionality. While prior work established the classical dynamics and effective field theory structure of STFO, a consistent formulation of quantum mechanics requires that quantum evolution be defined without reference to an external time parameter. In this work quantum mechanics is derived as unitary evolution along the temporal scalar field itself. Using a covariant path integral formulation, Schrödinger evolution is shown to arise as a gauge-fixed description of dynamics along the normalized temporal congruence. Measurement and the emergence of classical behavior follow from controlled temporal decoherence induced by EFT-suppressed matter couplings. The framework preserves standard quantum mechanics in weak-field regimes while predicting small, environment-dependent deviations accessible to precision experiments.Note:Earlier unified formulations of the Scalar Temporal Field Ontology admit an intrinsic ultraviolet regularization through nonlinear temporal feedback that dynamically saturates stress–energy. In the present phenomenological and quantum analyses, we work explicitly in the controlled low-energy effective limit of this theory, where predictions can be extracted and compared to observations without invoking the full ultraviolet dynamics.