Universal finite-size scaling amplitudes in anisotropic scaling

Phenomenological scaling arguments suggest the existence of universal ampli tudes in the finite-size scaling of certain correlation lengths in strongly anisotropic or dynamical phase transitions. For equilibrium systems, provi ded that translation invariance and hyperscaling are valid, the Privman-Fis her scaling form of isotropic equilibrium phase transitions is readily gene ralized. For non-equilibrium systems, universality: is shown analytically f or directed percolation and is tested numerically in the annihilation-coagu lation model and in the pair contact process with diffusion. In these model s, for both periodic and free boundary conditions, the universality of the finite-size scaling amplitude of the leading relaxation time is checked. Am plitude universality reveals strong transient effects along the active-inac tive transition line in the pair contact process.