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Sergei V. Ketov studied how curvature-driven cosmic inflation can arise within supergravity. With Alexei A. Starobinsky, he constructed an embedding of the $R+R^2$ inflationary model into an $N=1$ supergravity framework.^[ref]

Here $R$ denotes ordinary spacetime scalar curvature, while the supersymmetric construction uses a superfield extension. Relating the two descriptions is a model-building calculation; adding a curvature term to an action does not alone establish all of its supersymmetric couplings or the required slow-roll regime.