Bound on four-dimensional Planck mass

TL;DR

This paper derives a lower bound on the four-dimensional Planck mass using cosmic ray data, challenging models that lower the Planck scale to the TeV range without extra dimensions.

Contribution

It provides a model-independent limit on the four-dimensional Planck mass based on cosmic ray observations, specifically the non-detection of small black holes.

Findings

Lower bound of approximately 488 GeV on the Planck mass.

Constraints on TeV-scale gravity models without extra dimensions.

Implications for hierarchy problem solutions.

Abstract

In this note we derive a bound using data from cosmic rays physics on a model recently proposed to solve the hierarchy problem by lowering the Planck scale to the TeV region without the introduction of extra-dimensions. We show that the non observation of small black holes by AGASA implies a model independent limit for the four-dimensional reduced Planck mass of roughly 488 GeV.