The Nature of Pressure

In the Timothian Model, pressure is not a force acting across emptiness. It is the species-resolved isotropic push and mandatory backfill of a real, stratified chunk medium that permits no true vacuum. Different chunk species transmit pressure differently depending on size, density, mobility, lubrication, and pathway access; any pressure reading is therefore the net result of multiple partial contributions. Using this framing, this paper defines pressure in chunk terms and reinterprets classical hydrostatics and Bernoulli bookkeeping as summaries of species-resolved momentum exchange plus backfill constraints. The same mechanics explain drag, lift, stagnation, shocks, and the “sound barrier” as compatibility-debt events where imposed pressure maps outrun local repacking capacity, steepening into discontinuities and dissipating as heat. Cavitation is treated as a backfill-limited substitution regime (never literal emptiness), with material damage arising when sustained deficits are paid into boundaries via irreversible repacking, erosion, and pathway change. The paper also clarifies why “vacuum” gauges read gas partial pressure while the chunk medium remains present, and it recasts induction as equalization loops driven by time-varying pressure maps. The result stitches pressure to gravity, motion, thermodynamics, entropy, induction, and radioactive decay within one continuous Newtonian medium ontology. Part of the series "GUT Check: A Mechanical Grand Unification of Physics" https://www.timothian.institute I am open for discussion on Reddit at https://www.reddit.com/r/TimothianModel/