  Giant resonances of gravity Kaluza-Klein modes (with tensor couplings) in
high energy collisions are expected in the Randall-Sundrum orbifold model that
incorporates a plausible solution to the hierarchy problem. When the model is
extended to incorporate an exponentially small 4-D cosmological constant, the
KK spectrum becomes continuous, even in the compactified case. This is due to
the presence of a particle horizon, which provides a way to evade Weinberg's
argument of the need of fine-tuning to get a very small cosmological constant.
