This study investigated how exponential stability in impulsive delayed Cohen–Grossberg neural networks is reflected in the geometry of the error trajectory and in an auxiliary reaction–diffusion description. The analysis distinguished rigorous consequences of exponential stability from regular-point and finite-horizon geometric diagnostics. It was shown that exponential convergence of the error norm does not, in general, imply decay of the classical curvature. Instead, a speed-weighted curvature, representing the normal component of the error acceleration, satisfies an exponential upper bound under the stated higher-order regularity assumptions. An auxiliary reaction–diffusion model with multiplicative contractive impulses was then analysed by semigroup and Duhamel estimates, and a periodic Fourier-mode formulation was used to characterize transient rate matching between modal and forcing decay rates. Spectral graph estimates further provided a rigorous exponential envelope for the network disagreement energy. Numerical experiments supported these distinctions: The weighted-curvature diagnostic exhibited a fitted decay rate of $ 1.0478 $ with $ R^2 = 0.9914 $, while $ 456 $ of $ 500 $ Monte Carlo realizations satisfied the convergence criterion. The near-matching modal response had a peak ratio of $ 1.2553 $ relative to the selected detuned case, and the topology experiment detected statistically significant differences in both classical-curvature behavior and finite-horizon accumulated curvature. Overall, the results showed that norm stability rigorously controls weighted geometric and graph-energy quantities, whereas classical curvature and topology-dependent geometric effects should be interpreted as empirical finite-horizon diagnostics.
Citation: Gülden Altay Suroğlu, Münevver Tuz. Geometric trajectory stabilization and parabolic modal rate matching in impulsive delayed Cohen–Grossberg neural networks[J]. AIMS Mathematics, 2026, 11(8): 26470-26502. doi: 10.3934/math.20261062
This study investigated how exponential stability in impulsive delayed Cohen–Grossberg neural networks is reflected in the geometry of the error trajectory and in an auxiliary reaction–diffusion description. The analysis distinguished rigorous consequences of exponential stability from regular-point and finite-horizon geometric diagnostics. It was shown that exponential convergence of the error norm does not, in general, imply decay of the classical curvature. Instead, a speed-weighted curvature, representing the normal component of the error acceleration, satisfies an exponential upper bound under the stated higher-order regularity assumptions. An auxiliary reaction–diffusion model with multiplicative contractive impulses was then analysed by semigroup and Duhamel estimates, and a periodic Fourier-mode formulation was used to characterize transient rate matching between modal and forcing decay rates. Spectral graph estimates further provided a rigorous exponential envelope for the network disagreement energy. Numerical experiments supported these distinctions: The weighted-curvature diagnostic exhibited a fitted decay rate of $ 1.0478 $ with $ R^2 = 0.9914 $, while $ 456 $ of $ 500 $ Monte Carlo realizations satisfied the convergence criterion. The near-matching modal response had a peak ratio of $ 1.2553 $ relative to the selected detuned case, and the topology experiment detected statistically significant differences in both classical-curvature behavior and finite-horizon accumulated curvature. Overall, the results showed that norm stability rigorously controls weighted geometric and graph-energy quantities, whereas classical curvature and topology-dependent geometric effects should be interpreted as empirical finite-horizon diagnostics.
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