Energetics of quantum vacuum friction. II. Dipole fluctuations and field fluctuations

Quantum vacuum friction experienced by an atom, where the only dissipative mechanism is through its interaction with radiation field, has been studied in our recent paper [Phys. Rev. D 104, 116006 (2021)]. on intrinsically particle different that arises not from field fluctuations but also dipole intrinsic to particle. As a result, can be out of nonequilibrium steady state (NESS), and therefore loses or gains internal energy (rest mass). Only if temperature equals special NESS will NESS. In this paper, general conditions are derived which give as function velocity Imposing conditions, we obtain expression for quantum The shown negative definite (opposing motion particle) equivalent found previous dissipation restricted reaction. calculated numerically various models. particular, show that, gold nanosphere, deviation substantial it possible detect directly at sufficiently high temperatures. Out NESS, even though no longer sign rest frame radiation, still definite. Also, external force needed keep moving must same direction particle, excluding possibility perpetual machine, could convert into useful mechanical work. addition, find causes lose gain such way would return after deviating it. This enables experimental measurements serve feasible signature these frictional effects.