Kinks and small-scale structure on cosmic strings

TL;DR

This paper investigates the small-scale structure of cosmic strings, emphasizing the role of kinks and their sharpness distribution, and challenges previous models by proposing a linear variation of the tangent vector correlation at very small scales.

Contribution

It introduces the importance of kink sharpness distribution in understanding cosmic string small-scale structure and proposes a different scale dependence for the tangent vector correlation.

Findings

Kinks are crucial in small-scale structure of cosmic strings.

The tangent vector correlation varies linearly at very small scales.

The linear regime shrinks over time, aligning with previous models.

Abstract

We discuss some hitherto puzzling features of the small-scale structure of cosmic strings. We argue that kinks play a key role, and that an important quantity to study is their sharpness distribution. In particular we suggest that for very small scales the two-point correlation function of the string tangent vector varies linearly with the separation and not as a fractional power, as proposed by Polchinski and Rocha [Phys. Rev. D 74, 083504 (2006)]. However, our results are consistent with theirs, because the range of scales to which this linearity applies shrinks as evolution proceeds.