# n100 — THE AUDITOMETER: an instrument to distinguish the audited
# vacuum from general relativity (2026-07-10; instrument invention)

## The design brief
GR (any quantization): modulated mass-energy never decoheres anything.
The audited vacuum: decoherence with the universal Lorentzian profile
(dT00/dt)^2/(gamma^2+omega^2), knee predicted at gamma = alpha*mc^2/
hbar — electron anchor 5.7e18 s^-1 (soft X-ray). The instrument must
therefore do one thing no existing apparatus does: SWEEP T00-MODULATION
FREQUENCY THROUGH THE X-RAY BAND WHILE A MASSIVE SUPERPOSITION LISTENS.
The enabling coincidence: X-ray-rate energy modulation already exists
in laboratories — XFELs drive coherent electron-density oscillations
at 1e18-1e19 s^-1, exactly straddling the predicted knee.

## THE AUDITOMETER — pump-probe decoherometry
Three components:
1. THE PUMP (the T00 modulator): an X-ray free-electron laser driving
   a coherent charge/mass-density oscillation in a small target
   crystal — a localized region of intense, PHASE-COHERENT dT00/dt at
   sweepable frequency (fundamental + harmonics + two-color beats:
   1e17 -> 2e19 s^-1, crossing the electron-anchor knee).
2. THE PROBE (the listener): a matter-wave interferometer — heavy
   molecules or an atom fountain — whose two paths pass at different
   distances from the driven region. The observable: interference
   VISIBILITY as a function of pump frequency at fixed time-averaged
   (dT00/dt)^2 (amplitude compensated as frequency sweeps).
3. THE DISCRIMINATOR (the whole point): every conventional channel —
   photon scattering, thermal load, vibration, stray fields — either
   (a) tracks pump POWER, not pump FREQUENCY at fixed power, or
   (b) is shieldable/switchable (Faraday, cryo, vacuum). The audit
   channel is neither: it tracks the LORENTZIAN IN FREQUENCY and
   penetrates every shield, because it is not mediated — it is the
   vacuum's own bookkeeping. Signature: visibility loss rising as
   omega^2, kneeling at gamma, saturating — the same curve, at the
   same knee, for every probe species (universality check built in).
   GR's prediction across the entire sweep: a flat zero.

## THE KNEE LADDER — the poor man's version, running on existing tech
Instead of one sweepable pump: compare the ANOMALOUS dephasing budget
of internal-state superpositions across nature's frequency ladder,
which happens to straddle the predicted knee:
   hyperfine (6e10, weight 1e-16) -> optical clocks (2.7e15, 2e-7) ->
   Th-229 nuclear clock (1.3e16, 5e-6) -> XFEL-driven states (1.5e18,
   0.06) -> Moessbauer Fe-57 (2.2e19, 0.94) -> gamma isomers (1.5e20,
   ~1).
A superposition of internal energy eigenstates beats its T00 at the
transition frequency: the audit dephases it with the Lorentzian
weight. The theory predicts a SPECIFIC RATIO PATTERN of anomalous
linewidth contributions across the ladder (parameter-free once one
rung is measured); GR predicts zero anomalous contribution at every
rung. Today's data already whisper: optical clocks reach 1e-19
stability and Moessbauer lines reach natural width — both consistent
with the audit's per-quantum coupling being gravitationally small
(single-particle rates are hopeless; hence the Auditometer's
COLLECTIVE pump, where N ~ 1e20 electrons oscillate coherently and
the violation flux scales with the coherent amplitude squared).

## Honesty box
- Absolute rates are class [C] until the units bridge exists: the
  instrument's power is the SHAPE (the sweep, the knee, the
  universality across probes), which is parameter-free.
- The collective-enhancement factor (coherent N^2 vs incoherent N) in
  the violation flux is a modeling claim of the same class as the
  n48 toy — registered as the instrument's key theoretical risk.
- If the anchor is the proton (1e22 s^-1), the XFEL band sits BELOW
  the knee: the sweep then measures the omega^2 rise — still a
  nonzero, shaped signal vs GR's flat zero; the instrument
  discriminates under either anchor.
- A null at any achieved sensitivity is a real exclusion (bounds the
  audit's coupling at that frequency); a flat null across the band at
  sufficient sensitivity is the framework's funeral, as always.

## One sentence
Point the fastest coherent hammer we own (an XFEL) at the vacuum's
ledger, stand a matter-wave interferometer beside it, and sweep the
hammer's rhythm through soft X-ray: general relativity hears nothing
at any rhythm — the audited vacuum hears its own bookkeeping rate, and
answers with a Lorentzian whose knee is the fine-structure frequency
of the electron.