Steady-state work by an asymmetrically inelastic gravitator in a gas: A second law paradox

A new member of a growing class of unresolved second law paradoxes is exami ned.((1-7)) In a sealed blackbody cavity, a spherical gravitator is suspend ed in a low density gas. Infalling gas suprathermally strikes the gravitato r which is spherically asymmetric between its hemispheres with respect to s urface trapping probability for the gas. In principle, this system can be m ade to per form steady-state work solely at the expense of heat from the he at bath, this in apparent violation of the second law of thermodynamics. De tailed three-dimensional test particle simulations of this system support t his prediction. Standard resolutions to the paradox are discussed and found to be untenable. Experiments corroborating a central physical process of t he paradox are discussed briefly. The paradox is discussed in the context o f the Maxwell demon.