Abstract
We study \(\eta\) -Ricci–Yamabe solitons and gradient \(\eta\) -Ricci–Yamabe solitons in generalized Robertson–Walker space-times . At first, we provide an example of an \(\eta\) -Ricci–Yamabe soliton. Next, we prove that if a generalized Robertson–Walker space-time admits an \(\eta\) -Ricci–Yamabe soliton or a gradient \(\eta\) -Ricci–Yamabe soliton, then it becomes a perfect fluid space-time. As a consequence, we obtain several interesting corollaries.
