Temporal Flow Theory (TFT) unifies time, gravity, and quantum mechanics through an entropy flux four-vector Wµ, emergent from coarse-grained quantum entanglement and decoherence, coupled to spacetime curvature via a scale- and temperature-dependent function g(r,T). Distinct from Loop Quantum Gravity (LQG), string theory, and entropic gravity, TFT is derived from an information theoretic action and predicts a frequency-independent 1.0 ± 0.5% boost in the cosmic microwave background (CMB) power spectrum at ℓ ∼ 100, a Planck-scale bounce, a (1.0±0.2)×10−6 nanoscale quantum phase shift, and a (1.0 ± 0.3) × 10−16 gravitational wave (GW) speed deviation. These predictions are testable by CMB-S4, the Matter-wave Interferometer Gravitational-wave Antenna (MIGA), and LIGO/Virgo stacking, respectively. Consistent with Planck 2018 and GW170817 data, TFT operates as an effective field theory (EFT), offering a thermodynamically motivated resolution to the problem of time in quantum mechanics. This paper presents the full theoretical framework, including detailed derivations, cosmological implications, quantization, and experimental constraints, situating TFT within the broader quantum gravity landscape