Within the framework of unified approach we study the Casimir-Lifshitz interaction, the van der Waals friction force, and the radiative heat transfer at nonequilibrium conditions when the interacting bodies are at different temperatures and when they move relative to each other with the arbitrary velocity $V$. The analysis is focused on the surface-surface and surface-particle configurations. We show that relativistic effects give rise to a mixing of the contributions from the electromagnetic waves with different polarization to the heat transfer and the interaction forces. We find that these effects are of the order ${\left(V/c\right)}^2$. The limiting case when one of the bodies is sufficiently rarefied gives the heat transfer and the interaction forces between a moving small particle and a surface. We also calculate the friction force acting on a particle moving with an arbitrary velocity relative to the black body radiation.

• Received 6 July 2008

DOI:https://doi.org/10.1103/PhysRevB.78.155437