(De-)Stabilization of an extra dimension due to a Casimir force

by Ralf HOFMANN (MPI Munich)

Friday 8 Jun 2001, 14:00 → 15:00 Europe/Zurich

TH Auditorium (CERN)

We study the stabilization of one spatial dimension in (p+1+1) -dimensional spacetime in the presence of p-dimensional brane(s), a bulk cosmological constant and the Casimir force generated by a conformally coupled scalar field. We find general static solutions to the metric which require a fine tuning corresponding to a vanishing effective cosmological constant. Taking these solutions as a background configuration, we perform a dimensional reduction and study the effective theory in the case of one- and two-brane configurations. We show that the radion field can have a positive mass squared, which corresponds to a stabilization of the extra dimension, only for a repulsive nature of the Casimir force. This type of solution requires the presence of a negative tension brane. The solutions with one or two positive tension branes arising in this theory turn out to have negative radion mass squared, and therefore are not stable.