https://doi.org/10.1140/epjc/s10052-016-4094-9
Regular Article - Theoretical Physics
Soliton models for thick branes
1
Department of Physics, School of Sciences, Ferdowsi University of Mashhad, Mashhad, 91775-1436, Iran
2
Physics Department, Shahid Beheshti University, Evin, Tehran, 19839, Iran
3
Instituto de Astrofísica e Ciências do Espaço, Faculdade de Ciências da Universidade de Lisboa, Edifício C8, Campo Grande, 1749-016, Lisbon, Portugal
* e-mail: fslobo@fc.ul.pt
Received:
7
January
2016
Accepted:
15
April
2016
Published online:
2
May
2016
In this work, we present new soliton solutions for thick branes in dimensions. In particular, we consider brane models based on the sine-Gordon (SG),
and
scalar fields, which have broken
symmetry in some cases and are responsible for supporting and stabilizing the thick branes. The origin of the symmetry breaking in these models resides in the fact that the modified scalar field potential may have non-degenerate vacua. These vacua determine the cosmological constant on both sides of the brane. We also study the geodesic equations along the fifth dimension, in order to explore the particle motion in the neighborhood of the brane. Furthermore, we examine the stability of the thick branes, by determining the sign of the
term in the expansion of the potential for the resulting Schrödinger-like equation, where w is the five-dimensional coordinate. It turns out that the
brane is stable, while there are unstable modes for certain ranges of the model parameters in the SG and
branes.
© The Author(s), 2016