On the thin-string limit of the 6d stringlike defect model

Abstract

We show that in 6d models localizing gravity on stringlike defects and satisfying the dominant energy condition, the metric exterior to the string inevitably depends on the string's thickness. As a consequence, in the limit of thin string either the gravity delocalizes, or the six-dimensional Planck scale must be much larger that the four-dimensional one.

3 pages; v2: an alternative interpretation of our results, overlooked in the first version, is added