We derive upper and lower bounds for the spectral gap of the random en
ergy model under Metropolis dynamics which are sharp in exponential or
der. They are based on the Variational characterization of the gap. Fo
r the lower bound, a Poincare inequality derived by Diaconis and Stroo
ck is used. The scaled asymptotic expression is a linear function of t
he temperature. The corresponding function for a global version of the
dynamics exhibits phase transition instead. We also study the depende
nce of lower order terms on the volume. In the global dynamics, we obs
erve a phase transition. For the local dynamics, the expressions we ha
ve, which are possibly not sharp, do not change their order of depende
nce on the volume as the temperature changes.