 Randall–Sundrum model

A warped five-dimensional geometry redshifts masses of fields localized on the distant brane: $m_{\mathrm{IR}}=e^{-kL}{m}_0$. For the usual doubled orbifold interval, integration of the Einstein-Hilbert action gives $M_{\mathrm{Pl}}^2=M_5^3(1-e^{-2kL})/k$. Exponential redshift can generate a large separation of observable scales with a moderately sized dimensionless distance $kL$. Stabilizing the radion remains a dynamical requirement.

// Target: physics.bigb