{"artifact_id":"L1-067","layer":"L1","title":"Magnetoencephalography (MEG)","domain":"Medical Imaging","sub_domain":"Squid-array picotesla brain magnetic-field imaging","physics_fingerprint":{"L_DAG":4.5,"title":"Magnetoencephalography (MEG)","domain":"Medical Imaging","carrier":"radio_wave","primitives":["D.squid_array","L.inverse_source_localization","int.temporal"],"sub_domain":"Squid-array picotesla brain magnetic-field imaging","noise_model":"gaussian","problem_class":"nonlinear_inverse","solution_space":"4D_cortical_current","difficulty_delta":10,"integration_axis":"temporal","sensing_mechanism":"meg_squid_array"},"observable_profile":{"metric":"PSNR_dB","regime":"Existence of the recovered 4D cortical current 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 ~= 35); environmental_interference dominates the stability cliff; head_movement 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.","secondary":"SSIM"},"size_tiers":{"center_spec":{"omega":{"N_time":10000,"SNR_dB":15,"N_sensors":300,"sampling_Hz":1000,"head_movement":0.0,"sensor_crosstalk":0.0,"signal_space_leakage":0.0,"environmental_interference":0.05},"input_format":"measurement_only","problem_class":"meg","forward_operator":"meg_forward","epsilon_fn_center":"12.0"},"omega_bounds":{"N_time":[1000,1000000],"SNR_dB":[0.0,30.0],"N_sensors":[64,1024],"sampling_Hz":[100,10000],"head_movement":[0.0,0.3],"sensor_crosstalk":[0.0,0.3],"signal_space_leakage":[0.0,0.3],"environmental_interference":[0.0,0.5]},"epsilon_bounds":{"psnr_db":[5.0,45.0]},"allowed_problem_classes":["meg"],"allowed_omega_dimensions":["N_sensors","N_time","sampling_Hz","SNR_dB","environmental_interference","head_movement","sensor_crosstalk","signal_space_leakage","environmental_interference","head_movement","sensor_crosstalk","signal_space_leakage"],"allowed_forward_operators":["meg_forward"]},"hardness_fn":{"type":"epsilon_fn","delta":10,"kappa":700,"metric":"PSNR_dB"},"initiator_dataset":[{"name":"primary","weight":1.0,"ipfs_cid":null,"license_hash":null}],"status":"testnet","staked_pwm":0.0,"chain_hash":"0x940306eb01e02d05dc651802e650eb4d110655b0f5c7dcf54cd46b06ec34c91e","chain_tx_hash":"0x2e8e13ee7b12413e0ccf880d523b73323c42678e75d625de42c769deb114c3f4","chain_block":41553373}