Skobeltsyn Institute of Nuclear Physics
Lomonosov Moscow State University

We construct the second variation Lagrangian for Randall-Sundrum model
with two branes, study its gauge invariance, find the corresponding
equations of motion and decouple them. We also derive an effective Lagrangian
for this
model in the unitary gauge, which describes a massless graviton, massive
gravitons and a massless scalar radion. It is shown that the mass
spectra of these fields and their couplings to the matter are different
on different branes.