The analysis of fractional neutral stochastic differential equations in <inline-formula id="math-09-07-845-M1"><inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="math-09-07-845-M1.jpg"/></inline-formula> space

Abstract

<abstract><p>After extensive examination, scholars have determined that many dynamic systems exhibit intricate connections not only with their current and past states but also with the delay function itself. As a result, their focus shifts towards fractional neutral stochastic differential equations, which find applications in diverse fields such as biology, physics, signal processing, economics, and others. The fundamental principles of existence and uniqueness of solutions to differential equations, which guarantee the presence of a solution and its uniqueness for a specified equation, are pivotal in both the mathematical and physical realms. A crucial approach for analyzing complex systems of differential equations is the utilization of the averaging principle, which simplifies problems by approximating existing ones. Applying contraction mapping principles, we present results concerning the concepts of existence and uniqueness for the solutions of fractional neutral stochastic differential equations. Additionally, we present Ulam-type stability and the averaging principle results within the framework of <inline-formula id="math-09-07-845-M2"><inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="math-09-07-845-M2.jpg"/></inline-formula> space. This exploration involved the utilization of Jensen's, Gröenwall-Bellman's, Hölder's, Burkholder-Davis-Gundy's inequalities, and the interval translation technique. Our findings are established within the context of the conformable fractional derivative, and we provide several examples to aid in comprehending the theoretical outcomes.</p></abstract>