Chaos and universality in a four-dimensional spin glass

We present a finite-size scaling analysis of Monte Carlo simulation results on a four-dimensional Ising spin-glass. We study chaos with both coupling and temperature perturbations, and find the same chaos exponent in each case. Chaos is investigated both at the critical temperature and below where it seems to be more efficient (larger exponent). Dimension 4 seems to be above the critical dimension where chaos with temperature is no longer present in the critical region. Our results are consistent with the Gaussian and bimodal coupling distributions being in the same universality class.