The low temperature Monte Carlo dynamics of an ensemble of linear harm
onic oscillators shows some entropic barriers related to the difficult
y of finding the directions in configurational space which decrease th
e energy. This mechanism is enough to observe some typical non-equilib
rium features of glassy systems like activated-type behavior and aging
in the correlation function and in the response function. Due to the
absence of interactions the model only displays a one-step relaxation
process. (C) 1998 Elsevier Science B.V. All rights reserved.