On the Possible Anisotropy of the Unruh Radiation. Part I: Massless Scalar Field in (1+1)D Space-Time

Abstract

The Unruh effect for a massless scalar field in (1 + 1)D space-time is considered. It is shown that, under some natural assumptions like finiteness of the integration volume or finiteness of the interaction (propagation of information) speed, the Unruh effect should be anisotropic. This property is not connected with a particular detector design but is fundamental like the Unruh effect itself. This consideration can be generalized to the case of massless and massive particles in (3 + 1)D space-time. The obtained result and its further development may be important for specific applications of the Hawking-Unruh effect such as the description of black hole evaporation and motion dynamics of accelerated bodies.