  We investigate the role of Casimir energy as a mechanism for brane stability
in five-dimensional models with the fifth dimension compactified on an S^1\Z_2
orbifold, which includes the Randall-Sundrum two brane model (RS1). We employ a
zeta-function regularization technique utilizing the Schwinger proper time
method and the Jacobi theta function identity to calculate the one-loop
effective potential. We show that the combination of the Casimir energies of a
scalar Higgs field, the three generations of Standard Model fermions and one
additional massive non-SM scalar in the bulk produce a non-trivial minimum of
the potential. In particular, we consider a scalar field with a coupling in the
bulk to a Lorentz violating vector particle localized to the compactified
dimension. Such a scalar may provide a natural means of the fine-tuning needed
for stabilization of the brane spearation. Lastly, we briefly review the
possibility that Casimir energy plays a role in generating the currently
observed epoch of cosmological inflation by examining a simple five-dimensional
anisotropic metric.
