Substrate Ontology

What the engine mechanically expresses — measured, not asserted.

This is the Map (what exists) and the Compass (which way the loops run) for the meso3i engine, distilled from the E65–E90 experiments. (Archived engine record — the current engine's map lives in Moore26 Substrate.) Every claim traces to a measured signature; nothing here is an authored force.

The registers (what exists)

Register	Role	Gradient ends
mass[IMOV] + mass[REST]	mass quanta — channels = direction, REST = parked	moving ↔ parked
drest[IMOV]	directional-rest — channel-tagged stock	net-wound ↔ balanced-pair ↔ dead scalar (three ends)
iE	excitation/energy battery (≤255)	charged ↔ spent
iPT / iLT	link-load / latency cadence meters	busy ↔ quiet
phot[IMOV] (perf) / phot[IMOV×NNU] (meso3i)	photon flux; ν bins = transaction amount	hot (high ν) ↔ cold (ν=1)
iQ	bound-state register — dormant	unexplored

The conserved currency

Total quanta (mass + photons) are conserved — species interconvert at fusion/annihilation/absorb/emission forks. Measured closed ledger (E-series audits): seed = residue + drain + cap-loss.

The couplings (measured)

• Photon ↔ mass: absorb (charges iE), scatter (deflects), refuse (linkcap bounce/force-through)
• Photon → mass momentum: ablate (phot≥3) — radiation pressure, pushes lumps downstream (+3.7 sites, E84)
• Mass ↔ mass: accretion — mass flux deposits on the near face, drags centroid toward source (−9.4, E85). Light pushes, mass sticks — complementary transports
• Directional (dipole-analog): drest winding sets emission direction — anti-aligned wound lumps exchange flux, converge, outlast aligned (~19% slower decay, +3.7-site mutual pull, E82–83)

The feedback loops (signed)

• + retention: parked density ∝ iR → more arrivals park → denser (emergent gravity — dense retains 2.5× vs empty, E77)
• − depletion: iE spend quenches itself — every hot site cools; ν-spectrum is a depletion curve (E69–70)
• +/− species cycle: fusion (photons→mass) ↔ annihilation (drest pairs→photons) — interconversion
• + glow-trap: scatter traps photons in dense regions → more absorb → more iE → more emission (bounded by depletion)
• − saturation: linkcap refuses mass into photon-saturated sites — congestion self-limits

The dynamical fixpoints

• Static saturation: the clot — +/− loops balance, mass saturates to a ceiling (drain-vs-retention equilibrium)
• Frozen death: the remnant — +loop starved, activity front-loads then falls silent
• Periodic breathing: relaxation oscillator — iepush gives iE a spend channel; charge ramps, kick dumps, repeats. Sawtooth, tunable (E78): iepush 4/8/16 → iE ceiling ~3,050/2,900/ 2,500

The bound states (the deep finding)

• The bond is the exchange: gap iPT between two lumps holds separation while the photon bridge lives; merge follows the bridge's death, not attraction's win (E87)
• The repulsive core IS the photons: trapped gap photons push lumps apart (radiation pressure in the cavity). Attraction at range, photon pressure up close → equilibrium bond length ~24 sites (E88)
• Scale-free: pair → chain (~25–27 spacing, E89) → 2×2 plane (~33×24, E90) — matter with a natural lattice pitch, condensed matter emerging

What's deliberately absent

• Randomness: randmode=1 deterministic-phase mode reproduces the physics (E67) — dice were placeholder, not load-bearing
• Age: no register; nature's particles are indistinguishable — any "age" must be a state proxy (thermalization), not a clock
• Hard-coded spectrum: NNU dissolved — ν IS the transaction amount (E70), bounded by site charge not bin count
• Authored forces: every "force" measured is a routing/retention bias — gravity, radiation pressure, dipole coupling, bond equilibrium all emerge from the same ledger

Open frontiers

• iQ register — wired, never fires (capture conditions unprobed)
• Asymmetric-conversion lensing (edge-grazing beams depleting on the mass-facing side via catalyst-gated decay — predicted, faint)
• Winding exchange — spin transfer through mass accretion
• Whether any closed bound state truly self-sustains (the ground-state analog — a bond whose photons never leak)

New mechanics since E65 (all flag-gated, default off)

scatter± (deflect/toward-density), nuscat (spectral routing — hot flee/cold trap), lens± (avoid/attract — +72% mass held), randmode (deterministic phase picks — same physics, zero dice), iecost, iepush± (kick out/capture), linkcap± (refuse/force), massbnc (cap-refusal bounce), egate (density-gated boil-off — the flattened-dynamic fix), iget (arrival capacity gate), photdecay (catalyst-gated photon->mass, EMASK-mirrored, balanced), nuup (photon gains nu through hot sites — inverse-Compton).

Mechanics are ends of gradients — physics emerges where ends contest at shared junctions, not inside any single flag.