We investigate the creation of a brane world with a bulk scalar field. We consider an exponential potential of a bulk scalar field: , where β is the parameter of the theory. This model is based on a supersymmetric theory, and includes the Randall-Sundrum model (β = 0) and the five-dimensional effective model of the Horva-Witten theory (β = 1). We show that for this potential a brane instanton is constructed only when the curvature of a brane vanishes, that is, the brane is flat. We construct an instanton with two branes and a singular instanton with a single brane. The Euclidean action of the singular instanton solution is finite if β 2>2/3. We also calculate perturbations of the action around a singular instanton solution in order to show that the singular instanton is well defined.
- Cosmological phase transitions string theory and cosmology
- Cosmology with extra dimensions
ASJC Scopus subject areas
- Astronomy and Astrophysics