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arXiv · 2310.17619

Mimicking two field inflationary features with a single field

Abstract

It is well known that damped superimposed oscillations at large scales in the primordial power spectrum can be generated in both single field and two field models. In single field inflationary models, these features typically arise due to deviations from the slow roll regime. On the other hand, in two field models, these features are generated due to a turn in the background trajectory in the field space. In this work, we demonstrate that both single field and two field models can produce identical features at large scales in the primordial power spectrum. To achieve this, we utilize the generalized slow roll approximation and successfully reconstruct single field models based on the featured power spectrum typically generated in two field models. To validate our methodology, we numerically calculate the power spectrum from the reconstructed potential and find a remarkable agreement with the power spectrum which is obtained from the two field model.

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BibTeXRIS

Anvy Moly Tom, Rathul Nath Raveendran. 2023-10-26. Mimicking two field inflationary features with a single field. https://doi.org/10.1016/j.dark.2023.101343

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