Avoidance of naked singularities in dilatonic brane world scenarios with a Gauss–Bonnet term

We consider, in 5 dimensions, the low energy effective action induced by heterotic string theory including the leading stringy correction of order α′. In the presence of a single positive tension flat brane, and an infinite extra dimension, we present a particular class of solutions with finite 4-dimensional Planck scale and no naked singularity. A “self-tuning” mechanism for relaxing the cosmological constant on the brane, without a drastic fine tuning of parameters, is discussed in this context. Our solutions are distinct from the standard self-tuning solutions discussed in the context of vanishing quantum corrections in α′, and become singular in this limit.