# Fluctuations of gravitational waves in Eddington inspired Born-Infeld theory

## TL;DR

This paper reviews EiBI gravity with a cosmological constant, analyzing tensor perturbations and gravitational wave fluctuations, revealing a smooth transition from high to low energy densities and a spectrum with suppressed small-scale fluctuations.

## Contribution

It provides a detailed analysis of gravitational wave fluctuations in EiBI gravity, highlighting the transition between high-energy and low-energy regimes and deriving the graviton fluctuation spectrum.

## Key findings

- Existence of gravitational waves in the past-time within EiBI theory
- Smooth transition between high-energy EiBI dynamics and low-energy GR
- Fluctuation spectrum shows suppression at small k and vanishing at large k during De Sitter expansion

## Abstract

In this paper we review the EiBI gravity in the presence of a cosmological constant and its tensor perturbations analysis. We show the existence of gravitational waves in the past-time, seeing as a result the smooth transition between high-energy densities (where the EBI dynamics plays its role) and low-energy densities (GR). We obtain the fluctuation spectrum for the graviton in this theory, where for small values of k the fluctuations are strongly suppressed and for large values of k these fluctuations vanish during the De Sitter expansion.