Gravitational Waves generated during inflation from a 5D vacuum theory of gravity in a de Sitter expansion

TL;DR

This paper explores how gravitational waves are generated during inflation within a 5D vacuum gravity framework, aligning with standard 4D results and observational data.

Contribution

It demonstrates that a 5D vacuum theory of gravity can reproduce standard inflationary gravitational wave results on a 4D de Sitter background.

Findings

Amplitude of gravitational waves matches 4D inflationary predictions

Tensor-to-scalar ratio range agrees with COBE observations

Validates 5D vacuum approach for inflationary gravitational wave generation

Abstract

In this letter we study the generation of gravitational waves during inflation from a 5D vacuum theory of gravity. Within this formalism, on an effective 4D de Sitter background, we recover the typical results obtained with 4D inflationary theory in general relativity, for the amplitude of gravitational waves generated during inflation. We also obtain a range of values for the amplitude of tensor to scalar ratio which is in agreement with COBE observations.