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Photoacoustic Tomography (PAT) L1-041

Medical ImagingHybrid optical-acoustic absorption imagingδ=5 · challengingL_DAG = 4.2📋 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

Photoacoustic Tomography (PAT): photoacoustic pa produces the measurement through a 4-node primitive DAG L.laser_pulse_excite -> L.thermoacoustic_generation -> D.ultrasound_array -> int.temporal, with multi-angle tomographic integration and additive Gaussian thermal/electronic noise. Recovery is posed as a non-convex inverse problem that inverts the forward operator to estimate the scene-side 3D optical absorption. Difficulty tier delta=5 with effective condition number kappa_eff~22; calibration-level mismatch (sound_speed_heterogeneity, limited_view_geometry, laser_fluence_variation) sets the accuracy floor at the Omega boundary. See the forward_model field for the closed-form imaging equation.

L-DAG

L.laser_pulse_excite -> L.thermoacoustic_generation -> D.ultrasound_array -> int.temporal
L.laser_pulse_exciteL.thermoacoustic_generationD.ultrasound_arrayint.temporal

Well-posedness W

Existence:
true
Uniqueness:
true
Stability:
conditional
κ:
440

Existence of the recovered 3D optical absorption is guaranteed within the declared Omega bounds. Uniqueness is local rather than global (non-convex landscape); convergence depends on initialisation and priors. Stability is moderately conditioned (kappa_eff ~= 22); sound_speed_heterogeneity dominates the stability cliff; limited_view_geometry and the remaining mismatch parameters contribute higher-order bias terms. Additive gaussian thermal/electronic noise sets the irreducible data-fidelity floor, while TV / wavelet-sparsity / deep priors stabilise recovery at the ill-conditioned end of Omega.

Solvability C

Solver class:
linear-operator + convex optimisation [UBP, Model-Based-PA] | linear-operator + deep neural prior [PA-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.