Separability falsification · one IBM job, one quantum system

The primary architecture claim for QPC: when K objective contextures run coupled in one circuit, the measurement statistics show cross-context correlation that K independent IBM jobs miss. This page explains the task, the scoring, and the IBM Fez results from June 2026.

Plain English

What this test is
Separability falsification. One coupled IBM job (transjunctions ON) versus the same objectives as independent jobs (transjunctions OFF).
Why we did it
ICC is the falsification: joint structure the coupled arm can show, at matched readout.
What QPC computed
ICC (inter-context correlation) from raw shot counts at each context boundary. Same readout pipeline on both arms. Wiring is the independent variable.
Headline result
Toy instance 3/3 pass (gaps 0.052–0.106) · Cerrado real data gap 0.088 · part of JSC levels L1–L3 with public job IDs.
What we claim
Coupled runs show measurable joint structure on IBM Heron r2 (ibm_fez). Verification is via published job IDs and outcome tables.

Part of the Joint Structure Challenge (levels L1–L3). Level L4 (merge failure) is on the challenge hub.

The task

  1. Build a quantum circuit with three objective blocks (e.g. carbon, biodiversity, social).
  2. Coupled arm: connect blocks with transjunction gates → submit one job to IBM.
  3. Control arm: run each block alone (transjunctions off) → submit three jobs, then pair samples as independent.
  4. Ask: does the coupled run show extra correlation between adjacent objectives that the control misses?

When the gap is there, QPC is doing something quantum-joint: one circuit, one readout, joint structure the independent-job control misses.

Architecture metric: ICC. Portfolio / optimization scores sit on the Cerrado compare page.

How we score separability

We compare coupled (one IBM job, transjunctions on) vs separable control (independent jobs, samples paired as uncoupled). A proprietary inter-context correlation (ICC) witness is computed from shot statistics on aligned decision qubits at each context boundary. Both arms use identical readout and post-processing. Coupling is the difference.

Public pass criteria (outcomes only)

Exact ICC formula, readout schedule, and morphogram depth are proprietary. Independent verification uses published IBM job IDs below.

Toy soft-objective instance (15Q coupled, ibm_fez)

Synthetic three-contexture instance. Fixed seeds for reproducibility. 4096 shots each.

SeedICC gapCoupled ICCPassCoupled job ID
70.1060.114✓d8i3vdtv8cos73f549cg
110.0520.062✓ (rerun)d8i429dv8cos73f54e60
420.1040.112✓d8i3vu66983c73drmk10

Strong pass: 3/3 seeds.

Cerrado real data (Goiás carbon portfolio)

Same open dataset as Ribeiro 2026 (arXiv:2602.09047). Three objective contextures. Shared-layout and full-width Heron r2 jobs.

InstanceLayoutDepthMean ICC gapVerdictJob ID
n=8, k=3shared~5000.088Passd8i4065v8cos73f54a8g
n=12, k=4shared4740.088Passd8i42ic2upec739loi50
n=28, k=7full width13290.031Heron per-boundaryd8i44rc2upec739loktg

Full-width Heron r2, per-boundary readout (job d8i44rc2upec739loktg):

Transjunction boundaryCoupled ICCSeparable ICCGapPer-boundary
carbon ↔ biodiversity0.0050.010−0.005·
biodiversity ↔ social0.1100.0120.098✓
social ↔ carbon0.0030.0010.001·

Architecture finding at full Heron width: the biodiversity↔social bridge shows a raw ICC gap of 0.098 on ibm_fez. That is the joint-structure signal at 156Q for this instance.

What this demonstrates

Joint Structure Challenge → ← Architecture program overview Cerrado optimization compare →