We propose a conceptual and mathematical framework - the Theory of Temporal Flow (TTF) - in which time is modeled not as a passive coordinate dimension but as a physical fluid flowing from a higher-dimensional source into three-dimensional space. Space is conceived as a discrete, flexible grid of Planck-scale cells, each capable of exchanging a minimum quantum of temporal flow equal to the reduced Planck constant ħ.

From a single postulate - that the proper time rate of any object is inversely proportional to the local temporal flow density it interacts with - we derive, without additional assumptions: special-relativistic time dilation, gravitational time dilation (Schwarzschild metric), Newton's law of gravitation, the mass-energy equivalence E = mc², the Heisenberg uncertainty principle, quantization of particle masses, a finite vacuum energy, and exponential (de Sitter) expansion of the universe.

Mass is identified as frozen temporal flow - a topological knot in the spatial cell lattice - which creates a local flow deficit interpreted as gravity. Antimatter corresponds to flow frozen in the opposite phase. The universe originates as the interior of a black hole in a parent 4D space; black holes within our universe likewise generate nested daughter universes, yielding a fractal cosmological structure and a natural mechanism for fine-tuning of physical constants via cosmological natural selection (Smolin, 1992).

The theory predicts: the non-existence of negative mass, the impossibility of warp drives requiring exotic matter, and a finite, calculable vacuum energy density. Connections to Loop Quantum Gravity, Causal Dynamical Triangulations, and the braid model of particles (Bilson-Thompson, 2005) are identified.

Here is a hypothesis: Time as a physical fluid