title: Calculation of ground states of four-dimensional +/-J Ising spin glasses.
abstract: Ground states of four-dimensional (d=4) Edwards-Anderson Ising spin glasses are calculated for sizes up to 7 x 7 x 7 x 7 using a combination of a genetic algorithm and cluster-exact approximation. The ground-state energy of the infinite system is extrapolated as e0(infinity)=-2.095(1). The ground-state stiffness (or domain wall) energy Delta is calculated. A delta approximately L(theta(S)) behavior with theta(S)=0.64(5) is found which confirms that the d=4 model has an equilibrium spin-glass-paramagnet transition for nonzero T(c).
authors.affiliation: Institut für theoretische Physik, Bunsenstrasse 9, 37073 Göttingen, Germany. hartmann@theorie.physik.uni-goettingen.de
authors.forename: A K
authors.initials: AK
authors.lastname: Hartmann