Interferometric access gives shape without magnitude
no run lists this probe in builds_on:
builds_on: and related:The claim. A measurement that reads only a phase — an interference — recovers shape, not magnitude, because a phase is a difference and a difference is blind to a common offset. The clean instance: move the neutrino absolute mass scale by five orders of magnitude and the oscillation probability is identical to eight digits — oscillation sees only Δm², a difference, so the absolute level is invisible to it. Interference gives the pattern, never the level.
Provisional — not sealed, not scored
Falsifiable prediction. Any physical sector reachable only by interference is shape-rich and magnitude-poor — it yields ratios, differences and patterns in abundance and absolute scales not at all. Gravitational waves are the test that escapes it, and instructively: a chirp gives the mass (chirp mass) from shape — the time–frequency track — while the amplitude gives the luminosity distance. GW astronomy reads an amplitude as well as a phase, so it recovers a magnitude; a sector that read phase alone could not. The prediction fails if some interference-only observable delivers an absolute scale with no amplitude channel.
Placement. The interferometric face of §8.2's magnitude-vs-shape distinction: a bound gives a range without a value, interference a shape without a level. Cross-referenced to the bounding-mechanism table (docs/rung-vocabulary-v4-part1.md §8.2).
33 source lines, no addenda.