Inflaton Two-Point Correlation in the Presence of a Cosmic String

TL;DR

This paper investigates how the presence of an infinite cosmic string affects the two-point correlation function of the inflaton during inflation, potentially explaining observed anomalies in cosmic microwave background data.

Contribution

It introduces a model incorporating a cosmic string into inflationary perturbation calculations, revealing its impact on primordial density fluctuations.

Findings

Cosmic string modifies inflaton two-point correlation function.

Potential explanation for anomalies in CMB anisotropy.

Provides a framework for including topological defects in inflation models.

Abstract

Precise measurements of the microwave background anisotropy have confirmed the inflationary picture of approximately scale invariant, Gaussian primordial adiabatic density perturbations. However, there are some anomalies that suggest a small violation of rotational and/or translational invariance in the mechanism that generates the primordial density fluctuations. Motivated by this we study the two point correlation of a massless scalar (the inflaton) when the stress tensor contains the energy density from an infinitely long straight cosmic string in addition to a cosmological constant.