Semiclassical analysis of the tensor power spectrum in the Starobinsky inflationary model

TL;DR

This paper calculates the tensor power spectrum and tensor-to-scalar ratio in the Starobinsky inflationary model using advanced approximation methods, confirming results align with observational data.

Contribution

It introduces improved approximation techniques for analyzing the tensor spectrum in the Starobinsky model, providing consistent results with numerical and slow-roll methods.

Findings

Tensor-to-scalar ratio r matches observational intervals

Results are consistent across multiple approximation methods

Advanced methods improve analytical accuracy in inflationary models

Abstract

In this work we calculate the tensor power spectrum and the tensor-to-scalar ratio r within the frame of the Starobinsky inflationary model using the improved uniform approximation method and the third-order phase-integral method. We compare our results with those obtained with numerical integration and the slow-roll approximation to second order. We have obtained consistent values of r using the different approximations, and r is inside the interval reported by observations.