Causality of the Brane Universe - OPERA and ICARUS

TL;DR

This paper explores how causality is preserved in a brane universe model with a 5D Kaluza framework, explaining the absence of superluminal neutrino propagation in OPERA and ICARUS experiments.

Contribution

It demonstrates that a specific 5D Kaluza model can resolve causality issues and negate superluminal neutrino claims without requiring sterile neutrinos.

Findings

Causality violations are avoided in the 5D brane model.

Neutrino propagation remains subluminal in this framework.

Implications for neutrino experiments are clarified.

Abstract

The apparent violation of causality in the brane Universe can be avoided by taking the bulk spacetime modelled by a 5-dimensional Kaluza theory with factorizable ansatz for the 5-dimensional metric whose components do not depend on the fifth coordinate and with $G_{55}$ not a constant. The geodesic in the bulk does not correspond to a free particle. The Kaluza scalar makes it non-inertial. The implication on the neutrino experiment is that there is no superluminal propagation even after invoking sterile neutrinos.