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arXiv · 2306.07260

Constraints on the non-minimally coupled Witten-O'Raifeartaigh inflation

F. B. M. dos Santos·R. Silva·J. S. Alcaniz
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Abstract

We investigate the impact of a non-minimal coupling of the scalar field with gravity in inflationary models, where a small coupling is allowed. As a concrete example, we consider the Witten-O'Raifeartaigh model, where, in line with other models, the presence of a coupling strength $\xi$ can recover concordance of the inflationary parameters with cosmic microwave background (CMB) constraints, provided by the Planck collaboration. We go beyond the slow-roll regime and investigate the impact in the description of CMB anisotropies by performing a statistical analysis of the model with the most recent Planck + Baryon Acoustic Oscillations (BAO) data to seek for any indication of a non-zero coupling by data within the model. We find that not only the presence of a non-minimal coupling is seen, but the model has a slight statistical preference when compared with the standard $\Lambda$CDM one. We also discuss the results on the minimally-coupled model, which in general, favours the simple setting where the associated mass scale is equal to the reduced Planck mass $M_p$ while being, in general, disfavored concerning the standard model.

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F. B. M. dos Santos, R. Silva, J. S. Alcaniz. 2023-06-12. Constraints on the non-minimally coupled Witten-O'Raifeartaigh inflation. https://doi.org/10.1088/1475-7516%2F2023%2F07%2F027

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