We argue that spontaneous Lorentz violation may generally lead to metastable domain walls related to the simultaneous violation of some accompanying discrete symmetries. Remarkably, such domain-wall solutions exist for spacelike Lorentz violation and do not exist for the timelike violation. Because a preferred space direction is spontaneously induced, these domain walls have no planar symmetry and produce a peculiar static gravitational field at small distances, while their long-distance gravity appears the same as for regular scalar-field walls. Some possible applications of vector-field domain walls are briefly discussed.

• Received 8 January 2009

DOI:https://doi.org/10.1103/PhysRevD.80.065008