Eur. Phys. J. C 26, 473-478 (2003)
DOI: 10.1140/epjc/s2002-01076-3

Self-tuning and de Sitter brane intersections in 6-dimensional brane models

J. Jiang¹ and T. Li<sup>2

1</sup>  Department of Physics, University of Wisconsin-Madison, WI 53706, USA
²  Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104, USA

(Received: 8 November 2001 / Published online: 20 November 2002 )

Abstract
We study the self-tuning of general brane junctions and brane networks on 6-dimensional space-time. For general brane junctions, there may exist one fine-tuning among the brane tensions. For the brane networks, similar to the 5-dimensional self-tuning brane models, the brane tensions can be set arbitrarily and there exists a singularity for the metric and bulk scalar. If we want to regularize the singularity, we will introduce fine-tuning among the brane tensions. In addition, because the 4-dimensional cosmological constant we observe may be positive and very small, we discuss the brane network with de Sitter brane intersections by introducing a bulk scalar.

© Società Italiana di Fisica, Springer-Verlag 2003