23 in the determination of the Higgs mass m$_{h}$ ; three out of four of the remaining parameters can be expressed in terms of the three measured quantities that are customarily chosen as input parameters for the SM, α , G$_{F}$ and m$_{Z}$ using Eqs. (78),(79),(80). The free parameters of the model are then just πR and g$_{5}$ . The order of magnitude of πR is fixed by eq. (85) together with the request ¯ M ∼ TeV, while ¯ g$_{5}$ is constrained by eq. (65). In fact, since we need ˜ g 2 and ˜ g $^{′}$2 to be positive, eq. (65) implies ¯ g$_{5}$ > g, g ′ . We are now ready to calculate the spectrum. In the flat limit, the C and S functions (eq. (45)) reduce to ordinary trigonometric functions: C ( y, m ) = cos( my ) , S ( y, m ) = sin( my ) . However, even in this very simple case only the eigenvalue equation for the right charged sector (47) can be analytically solved. We get The equations (46), (48), defining the eigenvalues for the other two sectors, have to be solved numerically. Some general remarks can be made at a qualitative level, however. Eq. (46) can be recast in the form the eigenvalues of the left charged sector are then determined by the intersection of two curves: the trigonometric curve tan( mπR ) and the parabola − g 2 5 ˜ g 2 ( m 2 − ˜ g $^{2}$˜ v 2 4 ). The − ˜ g $^{2}$˜ v 2 4 term - originating from the y = πR brane mass term in the action (8) - raises the vertex of the parabola, allowing for an intersection of the curves near m = 0. The corresponding light eigenvalue m$_{L}$$_{0}$ can be identified with m$_{W}$ . For bigger values of m , the parabola goes down as − m $^{2}$, and the intersections are nearer and nearer the asymptotes of tan( mπR ) (which correspond to the zeroes of cos( mπR ), and thus to the eigenvalues of the right charged sector, Eq. (86)), that are evenly spaced by 1 /R . The situation is illustrated in Fig. 3. m$_{Ln}$ tan( m$_{Ln}$πR ) = − g 2 5 ˜ g $_{2}$( m 2 Ln − ˜ g $^{2}$˜ v 2 4 ); (87) m$_{Rn}$ = 2 n − 1 2 R , n = 1 , 2 , . . . (86)