Abstract

The present article introduces and investigates a class of implicit fractional differential equations with time-varying state-dependent feedback, a setting that significantly extends existing fractional delay models. Existence and uniqueness results are established via the Banach fixed-point theorem, while sharp exponential growth estimates for the solutions are derived using a generalized Gronwall-type inequality. These results provide new analytical insights into the qualitative behavior of fractional systems with dynamically evolving feedback mechanisms.

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