Abstract In this work, we investigate the possibility of generating an inflationary mechanism within the framework of a metric- f ( R ) modified gravity theory, formulated in the Jordan frame. We explore whether the scalar field, non-minimally coupled to gravity and emerging in the Jordan frame, can play the role of the primordial inflaton. Particular attention is devoted to constructing a dynamical scenario in the Jordan frame that exhibits a slow-rolling phase for the scalar field and admits a quasi-de Sitter solution for cosmic evolution. To ensure consistency with the standard cosmological model, we impose a matching condition with the ΛCDM model at the end of the inflationary phase. Furthermore, to address the problem of the absence of matter after inflation, we consider a radiation-type particle creation process that maintains an approximately constant energy density. We test our theoretical model against background observational data, specifically Pantheon + calibrated with SH0ES and DESI calibrated with BBN. We asses the model's viability by combining theoretical consistency tests with its predictions for primordial power spectrum observables, and we discuss the implications for alleviating the Hubble constant tension.
Fazzari et al. (Wed,) studied this question.