Abstract
We have studied the three-dimensional Ising spin glass with a $\pm J$
distribution by Monte Carlo simulations. Using larger sizes and
much better statistics than in earlier work, a finite size scaling
analysis shows quite strong evidence for a finite transition
temperature, $T_c$, with ordering below $T_c$. Our estimate of the
transition temperature is rather lower than in
earlier work, and the value of the correlation length exponent, $\nu$, is
somewhat higher. Because there may be (unknown) corrections to
finite size scaling, we do not completely rule out the possibility
that $T_c = 0$ or that $T_c$ is finite but with no order below $T_c$. However,
from our data, these possibilities seem less likely.