{ "seed": 1418, "linear_contraction_sweep": { "predicted_stability_boundary_g2": 2.0, "observed_first_grid_stable_g2": 2.0500000000000003, "grid_step": 0.05, "projected_H": 0.5, "checks": { "1.5": { "spectral_abscissa": 0.28077640640441515, "log_norm_slope": 0.28506515724491827, "norm_t0": 1.4142135623730951, "norm_t8": 13.920981013765749 }, "3.0": { "spectral_abscissa": -0.7499999999999999, "log_norm_slope": -0.7524656038095815, "norm_t0": 1.4142135623730951, "norm_t8": 0.012201718698289765 } } }, "gain_sweep": [ { "g2": 0.0, "full_abscissa": 0.8507810593582121, "projected_H": 0.5 }, { "g2": 0.25, "full_abscissa": 0.770690632574555, "projected_H": 0.5 }, { "g2": 0.5, "full_abscissa": 0.6861406616345072, "projected_H": 0.5 }, { "g2": 0.75, "full_abscissa": 0.596291201783626, "projected_H": 0.5 }, { "g2": 1.0, "full_abscissa": 0.5, "projected_H": 0.5 }, { "g2": 1.25, "full_abscissa": 0.39564392373896, "projected_H": 0.5 }, { "g2": 1.5, "full_abscissa": 0.28077640640441515, "projected_H": 0.5 }, { "g2": 1.75, "full_abscissa": 0.15138781886599734, "projected_H": 0.5 }, { "g2": 2.0, "full_abscissa": 0.0, "projected_H": 0.5 }, { "g2": 2.25, "full_abscissa": -0.19098300562505255, "projected_H": 0.5 }, { "g2": 2.5, "full_abscissa": -0.4999999999999999, "projected_H": 0.5 }, { "g2": 2.75, "full_abscissa": -0.7499999999999998, "projected_H": 0.5 }, { "g2": 3.0, "full_abscissa": -0.7499999999999999, "projected_H": 0.5 }, { "g2": 3.25, "full_abscissa": -0.7499999999999999, "projected_H": 0.5 }, { "g2": 3.5, "full_abscissa": -0.7500000000000001, "projected_H": 0.5 }, { "g2": 3.75, "full_abscissa": -0.75, "projected_H": 0.5 }, { "g2": 4.0, "full_abscissa": -0.75, "projected_H": 0.5 } ], "euler_stability_sweep": { "g2": 3.0, "eigenvalues": [ [ -0.7499999999999999, 0.6614378277661476 ], [ -0.7499999999999999, -0.6614378277661476 ] ], "predicted_dt_max": 1.5000000000000002, "observed_dt_max_grid": 1.4989999999999999, "dt_grid": 0.001 }, "lorenz_partial_observation": { "open_loop": { "initial_error": 20.149441679609886, "final_error": 30.97985872769628, "median_last_20pct": 14.828022853040249 }, "nudging": { "initial_error": 20.149441679609886, "final_error": 0.12642521488225347, "median_last_20pct": 0.14382116971552625 } }, "interpretation": { "prediction_1": "Full 2D observer stability begins at g2=2 from det(A-GC)>0; observed grid boundary should agree.", "prediction_2": "At stable g2=3, Euler stability has a finite dt boundary predicted by -2 Re(lambda)/|lambda|^2; observed sweep should agree.", "prediction_gain": "Projected H remains +0.5 across all gains, while full abscissa crosses zero at g2=2; this falsifies H-only sufficiency here.", "prediction_3": "The proposed H on ker(C) remains +0.5 for every gain, despite full observer becoming stable; therefore the stated projected certificate is not sufficient in this coupled example." } }