Signatures in the Planck Regime

TL;DR

This paper explores how a generalized uncertainty principle, inspired by string theory and extra dimensions, conceals short-distance physics below the lowered Planck scale, impacting collider and cosmic ray experiments.

Contribution

It introduces a model where the generalized uncertainty principle hides physics below the TeV-scale Planck length, affecting experimental signatures.

Findings

Short distance physics below 1/MeV is cloaked by the uncertainty principle.

Predicted modifications to $e^+e^- o f^+f^-$ cross-sections.

Planckian effects could be observable at future colliders and in cosmic rays.

Abstract

String theory suggests the existence of a minimum length scale. An exciting quantum mechanical implication of this feature is a modification of the uncertainty principle. In contrast to the conventional approach, this generalised uncertainty principle does not allow to resolve space time distances below the Planck length. In models with extra dimensions, which are also motivated by string theory, the Planck scale can be lowered to values accessible by ultra high energetic cosmic rays (UHECRs) and by future colliders, i.e. $M_f\approx$ 1 TeV. It is demonstrated that in this novel scenario, short distance physics below $1/M_f$ is completely cloaked by the uncertainty principle. Therefore, Planckian effects could be the final physics discovery at future colliders and in UHECRs. As an application, we predict the modifications to the $e^+e^- \to f^+f^-$ cross-sections.