Short Distance Physics of the Inflationary de Sitter Universe

TL;DR

This paper explores how a generalized uncertainty principle affecting scalar fields in de Sitter space modifies inflationary predictions, especially the tensor-to-scalar ratio, and compares these with Planck data to constrain quantum gravity effects.

Contribution

It introduces a GUP with linear momentum terms into inflationary cosmology and analyzes its effects on scalar and tensor modes in de Sitter space.

Findings

Modified tensor-to-scalar ratio due to GUP effects

Constraints on the minimum length parameter from Planck data

Insights into quantum gravity implications for inflation

Abstract

In this work, we investigate inflationary cosmology using scalar field theory deformed by the generalized uncertainty principle (GUP) containing a linear momentum term. Apart from being consistent with the existence of a minimum measurable length scale, this GUP is also consistent with doubly special relativity and hence with the existence of maximum measurable momentum. We use this deformed scalar field theory to analyze the tensor and scalar mode equations in a de Sitter background, and to calculate modifications to the tensor-to-scalar ratio. Finally, we compare our results for the tensor-to-scalar ratio with the Planck data to constrain the minimum length parameter in the GUP.