Ulam–Hyers–Rassias stabilities of nonlinear fractional differential equations

This study investigates the Ulam–Hyers, Ulam–Hyers–Rassias, and $$\sigma $$ –semi–Ulam–Hyers stabilities of nonlinear fractional differential equations involving the Riemann–Liouville fractional derivative. The analysis is carried out by employing the Bielecki–type metric together with Banach’s fixed–point theorem. Both finite and infinite interval cases are explored, and several illustrative examples are provided to demonstrate the obtained findings.