= (z)\^[3/2]{} \_n \^[n]{}\_[L,R]{}(x) \^[(n)]{}\_[L,R]{} (z)  . The wave functions are given by combinations of Bessel functions g\^[(n)]{}(z) & = & N\_n z . \[eq:KKgluon\] with normalization factor $N_n$ and admixture controlled by $b_n$. The mass spectrum is controlled by the boundary conditions, with the masses satisfying, b\_n = - = -  . \[eq:b0\] For an unbroken gauge group, there is a zero mode with wave function $g^0(z) = 1 / \sqrt{L}$, $L = 1/k \log z_v / z_h$. Of particular note for the following is the fact that the light KK states have most of their support close to the IR boundary.

The physics of bulk fermions was worked out in [@Grossman:1999ra]. The spectrum depends sensitively on the bulk mass term $c$. To remove unwanted light degrees of freedom, we impose the boundary conditions such that either the right- or the left-chiral zero mass component is projected out. The KK states form left- and right-chiral pairs whose wave functions are also Bessel functions, \^[(n)]{}\_ (z) = [N]{}\_n (z) , \[eq:fermion\] where $-~(+)$ are for the right- (left-) chiral modes, and the masses are determined by imposing the equality, \_n & = & =  , and ${\cal N}_n$ is a 