Comment on "Testing Planck-Scale Gravity with Accelerators"

TL;DR

This paper critiques a previous study on testing Planck-scale gravity with accelerators, arguing that the parameter space claimed to be testable is already experimentally excluded by existing observations such as vacuum Cherenkov radiation.

Contribution

It provides a critical analysis showing that the parameter domain considered in the prior work is already ruled out by existing experimental constraints.

Findings

The domain of quantum gravity parameters tested is experimentally excluded.

Existing observations like vacuum Cherenkov radiation constrain quantum gravity models.

The previous analysis overestimates the testability of Planck-scale gravity with current accelerators.

Abstract

We challenge the analysis and conclusions of the paper Phys. Rev. Lett. 109, 141103 (2012) by V. Gharibyan on the tests of Planck-scale gravity with accelerators. The main objective of the Comment is the observation that the explored domain of "quantum gravity" parameters is already ruled out experimentally from, e.g., absence of the vacuum Cherenkov radiation.