Superluminal propagation on a moving braneworld

Authors

Brian Greene, Columbia University
Daniel Kabat, CUNY Lehman CollegeFollow
Janna Levin, Barnard College
Arjun S. Menon, Horace Greeley High School

Document Type

Article

Publication Date

2022

Abstract

We consider a braneworld scenario in the simplest setting, M₄ × S¹, with a four-dimensional (4D) Minkowski metric induced on the brane, and establish the possibility of superluminal propagation. If the brane is at rest, the 4D Lorentz symmetry of the brane is exact, but if the brane is in motion, it is broken globally by the compactification. By measuring bulk fields, an observer on the brane sees a slice through a higher-dimensional field profile, which carries an imprint of the extra dimensions even when the brane is at rest. If the brane is in motion, we find that bulk fields can propagate outside the brane light cone by a parametrically large amount set by the brane velocity. We mention observational tests and possible applications to cosmology.

Comments

This article was originally published in Physical Review D, available at https://doi.org/10.1103/PhysRevD.106.085001

This work is distributed under a Creative Commons Attribution 4.0 International License (CC BY 4.0).