Dark Matter as an Ad Hoc Paradigm Patch: Galactic Rotation Curves and Metric Monism within Time Field Theory (TFT)

The galactic rotation curve anomaly is commonly interpreted as evidence for dark matter. This work proposes an alternative interpretation rooted in the ontological framework of Time Field Theory (TFT). From the perspective of periodic metric monism, the mismatch between observed rotation velocity and classical gravitational prediction arises from a systematic measurement bias caused by variable local metric benchmarks, rather than unseen massive particles. We conduct a systematic comparison among three frameworks: the dark matter paradigm, Modified Newtonian Dynamics (MOND), and TFT. Unlike dark matter theory which introduces unobserved material entities, and MOND which modifies gravitational dynamics empirically, TFT derives galactic rotation behavior directly from fundamental self-consistency constraints of periodic spacetime without any free adjustable parameters. The logical structure repeated in the history of physics — geocentric epicycles, luminiferous ether, and dark matter — demonstrates that ad hoc invisible entities are often temporary supplements for defective underlying ontological presuppositions. Within TFT, the varying rate of periodic oscillators establishes the only primitive physical benchmark; spatial scale is a derived quantity. Gravity corresponds to the gradient of periodic rate distribution. Once the metric benchmark variation is fully incorporated into calculations, the galactic rotation discrepancy vanishes naturally. This result shows that TFT uniformly accounts for solar system gravitational tests, black hole phenomena, galactic rotation curves and cosmological tension within a single self-consistent axiom system, without introducing new hypothetical entities or empirical correction rules.