{"artifact_id":"L1-397","layer":"L1","title":"FitzHugh-Nagumo Excitability Model","domain":"Computational Biology","sub_domain":"Neural excitability","physics_fingerprint":{"L_DAG":2.5,"title":"FitzHugh-Nagumo Excitability Model","domain":"Computational Biology","carrier":"N/A","primitives":["D.time","O.chi2.phase_portrait","S.continuation.bifurcation"],"sub_domain":"Neural excitability","noise_model":"gaussian","problem_class":"parameter_estimation","solution_space":"FHN_parameter_vector","difficulty_delta":3,"integration_axis":"time","sensing_mechanism":"action_potential_recording"},"observable_profile":{"metric":"phase_portrait_RMSE","regime":"Existence of the recovered FHN_parameter_vector is guaranteed within the declared Omega bounds. Uniqueness holds on the measurement-supported subspace; out-of-support modes are controlled by declared priors. Stability is conditionally stable (kappa_eff ~= 50); noise_amplitude dominates the stability cliff; the remaining mismatch parameters contribute higher-order bias terms. Gaussian sets the irreducible data-fidelity floor.","secondary":"bifurcation_point_error"},"size_tiers":{"center_spec":{"omega":{"b_recovery":0.8,"a_threshold":0.7,"noise_sigma":0.0,"epsilon_timescale":0.08},"input_format":"measurement_only","problem_class":"parameter_estimation","forward_operator":"action_potential_recording","epsilon_fn_center":"0.05 phase_portrait_RMSE"},"omega_bounds":{"b_recovery":[0.5,1.5],"a_threshold":[0.5,1.5],"noise_sigma":[0.0,0.5],"epsilon_timescale":[0.01,0.5]},"epsilon_bounds":{"phase_portrait_RMSE":[0.005,0.3]},"allowed_problem_classes":["parameter_estimation"],"allowed_omega_dimensions":["a_threshold","b_recovery","epsilon_timescale","noise_sigma"],"allowed_forward_operators":["action_potential_recording"]},"hardness_fn":{"type":"epsilon_fn","delta":3,"kappa":1000,"metric":"phase_portrait_RMSE"},"initiator_dataset":[{"name":"primary","weight":1.0,"ipfs_cid":null,"license_hash":null}],"status":"testnet","staked_pwm":0.0,"chain_hash":"0x0f0efe82f19e8d237278873f54b39dce08570a944fd6e45f0603e19bd0b77e09","chain_tx_hash":"0x3b1a85302d1679b27651f4b43eaa418a7328c603470d6d53948b62e99fb1717b","chain_block":41555199}