3^He A-B Transition in Finite Geometries

The measured rate of the 3^He A-B transition depends on the diameter of the experimental cell. Theoretically, this can only be explained by a direct drag on the interface exerted by the lateral walls, leading to a pressure discontinuity across the interface. This has not been considered before, either here or in similar circumstances. The general hydrodynamic theory that includes the influence of finite geometries is presented.