Does a Randall-Sundrum scenario create the illusion of a torsion-free universe?

TL;DR

This paper explores how a Randall-Sundrum model with bulk torsion, represented by the Kalb-Ramond field, can explain the apparent absence of torsion effects in our universe due to exponential suppression of zero modes.

Contribution

It introduces a model where torsion exists in the bulk of a Randall-Sundrum scenario and shows how its zero mode is naturally suppressed on the visible brane, explaining the illusion of a torsion-free universe.

Findings

Torsion zero mode is exponentially suppressed on the brane.

Massive torsion modes could be detectable at TeV-scale experiments.

Torsion effects are weaker than curvature effects due to bulk suppression.

Abstract

We consider spacetime with torsion in a Randall-Sundrum (RS) scenario where torsion, identified with the rank-2 Kalb-Ramond field, exists in the bulk together with gravity. While the interactions of both graviton and torsion in the bulk are controlled by the Planck mass, an additional exponential suppression comes for the torsion zero-mode on the visible brane. This may serve as a natural explanation of why the effect of torsion is so much weaker than that of curvature on the brane. The massive torsion modes, on the other hand, are correlated with the corresponding gravitonic modes and may be detectable in TeV-scale experiments.