  We introduce a simple two-dimensional spin model with short-range
interactions which shows glassy behavior despite a Hamiltonian which is
completely homogeneous and possesses no randomness. We solve exactly for both
the static partition function of the model and the distribution of energy
barriers, giving us the equilibration time-scales at low temperature.
Simulations of instantaneous quenches and of annealing of the model are in good
agreement with the analytic calculations. We also measure the two-time spin
correlation as a function of waiting time, and show that the model has aging
behavior consistent with the distribution of barrier heights. The model appears
to have no sharp glass transition. Instead, it falls out of equilibrium at a
temperature which decreases logarithmically as a function of the cooling time.
