Detecting Vanishing Dimensions Via Primordial Gravitational Wave Astronomy

TL;DR

This paper proposes a method to test the hypothesis of vanishing dimensions at high energies by detecting a maximum frequency cutoff in primordial gravitational waves, which could be observed by future detectors like LISA.

Contribution

It introduces a novel test for vanishing dimensions using gravitational wave frequency cut-offs, linking high-energy physics with gravitational wave astronomy.

Findings

A maximum frequency cutoff in primordial gravitational waves is predicted.

Future detectors like LISA could observe this frequency cutoff.

The approach provides a new way to test theories of dimensional reduction at high energies.

Abstract

Lower-dimensionality at higher energies has manifold theoretical advantages as recently pointed out. Moreover, it appears that experimental evidence may already exists for it - a statistically significant planar alignment of events with energies higher than TeV has been observed in some earlier cosmic ray experiments. We propose a robust and independent test for this new paradigm. Since (2+1)-dimensional spacetimes have no gravitational degrees of freedom, gravity waves cannot be produced in that epoch. This places a universal maximum frequency at which primordial waves can propagate, marked by the transition between dimensions. We show that this cut-off frequency may be accessible to future gravitational wave detectors such as LISA.