The dark dimension, the Swampland, and the origin of cosmic rays beyond the GZK barrier

TL;DR

This paper proposes testing the existence of a hypothesized dark dimension, suggested by Swampland and cosmological hierarchy considerations, through observations of ultra-high-energy cosmic rays.

Contribution

It introduces a novel experimental approach to detect the dark dimension by analyzing the behavior of the highest energy cosmic rays.

Findings

Potential to confirm the dark dimension via cosmic ray observations

Links Swampland ideas with observable cosmic phenomena

Provides a testable prediction for extra-dimensional theories

Abstract

Very recently, it was pointed out that when basic ideas of the Swampland program are combined with the cosmological hierarchy problem (i.e. the smallness of the dark energy in Planck units) and together are confronted to experiment lead to the prediction of the existence of a single extra-dimension (dubbed the dark dimension) with characteristic length-scale in the micron range. We propose a feasible test procedure to probe the dark dimension using the highest energy cosmic rays.