Brane world regularization of point particle classical self-energy

TL;DR

This paper demonstrates that scalar particles in brane world models have finite self-energies and nonsingular potentials, using deviations from Coulomb's law to set experimental bounds on the model's parameters.

Contribution

It extends previous work by showing scalar particles also have finite self-energy and nonsingular potentials in brane models, similar to electromagnetic cases.

Findings

Scalar particles produce finite self-energy.

Deviations from Coulomb potential set bounds on AdS radius.

Bounds are less strict than those from Lamb shift experiments.

Abstract

Physical effects in brane worlds models emerge by the incorporation of field modes coming from extra dimensions with the usual four dimensional ones. Such effects can be tested with well established experiments to set bounds on the parameters of the brane models. In this work we extend a previous result which gave finite electromagnetic potentials and self energies for a source looking pointlike to an observer sitting in a 4D Minkowski subspace of a single brane of a Randall-Sundrum spacetime including compact dimensions, and along which the source stretches uniformly. We show that a scalar particle produces a nonsingular static potential, possess a finite self-energy and that technically its analysis is very similar to the electrostatic case. As for the latter, we use the deviations from the Coulomb potential to set bounds on the anti de Sitter radius of the brane model on the basis of two experiments, namely, one of the Cavendish type and other being the scattering of electrons by Helium atoms. We found these are less stringent than others previously obtained using the Lamb shift in Hydrogen.