Eur. Phys. J. C (2015) 75: 139
https://doi.org/10.1140/epjc/s10052-015-3362-4

Regular Article - Theoretical Physics

Crosstalk between DGP branes

¹ Department of Physics and Engineering Physics, University of Saskatchewan, 116 Science Place, Saskatoon, SK, S7N 5E2, Canada
² Perimeter Institute for Theoretical Physics, 31 Caroline Street North, Waterloo, ON, N2L 2Y5, Canada

^* e-mail: rainer.dick@usask.ca

Received: 12 February 2015
Accepted: 18 March 2015
Published online: 26 March 2015

Abstract

If two DGP branes carry gauge theories and overlap, particles of one brane can interact with the photons from the other brane. This coupling modifies in particular the Coulomb potentials between charges from the same brane in the overlapping regions. The coupling also introduces Coulomb interactions between charges from the different branes which can generate exotic bound states. The effective modification of the fine structure constant in the overlap region generates a trough in signals at the redshift of the overlap region and an increase at smaller or larger redshift, depending on the value of the crosstalk parameter . This implies potentially observable perturbations in the Lyman forest if our 3-brane overlapped with another 3-brane in a region with redshift . Crosstalk can also affect structure formation by enhancing or suppressing radiative cooling.