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SPECT-CT Fusion L1-158

Multimodal FusionHybrid gamma-camera + X-ray CTδ=3 · standardL_DAG = 3.3📋 Stub — not mineable
📋

Unclaimed Principle — open for contribution

This Principle is declared in the catalog but has no reference solver, no pinned dataset, and is not registered on-chain. There is no reward pool. Submitting a cert against this Principle today will record the cert for reproducibility but pay zero PWM.

To claim it as a Bounty #7 contribution: open a PR adding (1) a reference solver, (2) ≥1 dataset pinned to IPFS, (3) updates to the L3 manifest with dataset CIDs. After verifier-agent triple-review, the founders' 3-of-5 multisig signs PWMRegistry.register() and the Principle becomes mineable.

Forward model E

SPECT-CT Fusion: spect ct fusion produces the measurement through a 4-node primitive DAG L.ct_attenuation_map -> L.spect_activity_map -> L.registration -> int.spatial, with spatially-projected accumulation and additive Gaussian thermal/electronic noise. Recovery is posed as a linear inverse problem that inverts the forward operator to estimate the scene-side 3D fused activity anatomy. Difficulty tier delta=3 with effective condition number kappa_eff~13; calibration-level mismatch (registration_error, patient_motion, attenuation_correction_bias) sets the accuracy floor at the Omega boundary. See the forward_model field for the closed-form imaging equation.

L-DAG

L.ct_attenuation_map -> L.spect_activity_map -> L.registration -> int.spatial
L.ct_attenuation_mapL.spect_activity_mapL.registrationint.spatial

Well-posedness W

Existence:
true
Uniqueness:
true
Stability:
conditional
κ:
260

Existence of the recovered 3D fused activity anatomy is guaranteed within the declared Omega bounds. Uniqueness holds on the measurement-supported subspace; out-of-support modes are controlled by the declared priors. Stability is moderately conditioned (kappa_eff ~= 13); registration_error dominates the stability cliff; patient_motion and the remaining mismatch parameters contribute higher-order bias terms. Additive gaussian thermal/electronic noise sets the irreducible data-fidelity floor, while mild Tikhonov or analytic inversion is sufficient at the nominal Omega point.

Solvability C

Solver class:
linear-operator + convex optimisation [Rigid-Reg, AC-OSEM] | linear-operator + deep neural prior [SPECT-CT-Net]
Convergence rate q:
2
Complexity:
O(H * W * Z * log(...)) per iteration; learned variants: O(H W Z * F_theta_cost) per forward pass

Specs (0)

No L2 specs registered yet for this principle.