Breathing mode compactifications and supersymmetry of the brane-world Original Research Article

It has recently been shown that the Randall–Sundrum brane-world may be obtained from an appropriate doubled D3-brane configuration in type IIB theory. This corresponds, in five dimensions, to a sphere compactification of the original IIB theory with a non-trivial breathing mode supporting the brane. In this paper, we shall study the supersymmetry of this reduction to massive five-dimensional supergravity, and derive the effective supersymmetry transformations for the fermionic superpartners to the breathing mode. We also consider the sphere compactifications of eleven-dimensional supergravity to both four and seven dimensions. For the compactifications on S5 and S7, we include a squashing mode scalar and discuss the truncation from N=8 to N=2 supersymmetry.