Heat radiation @ near and far

red ball  Radiation Pressure from a hot-plate can in principle counteract Casimir attraction

Hieronymus-Bosch,-The-Last-Judgement.-Central-Panel-with-Detail-of-Heaven      

yellow ball  Stefan-Boltzmann law suggest that heat transfer between two bodies is independent of their separation. Is this true?

red ball Breaking the law, at the nanoscale (MIT news, July 29, 2009)  S. Shen, A. Narayanaswamy, & G. Chen, Nano Lett. 9, 2909 (2009)

 

red ball Near-field effects: At short separations heat exponentially decaying evanescent waves are dominant sources of heat transfer and pressure.

yellow ball For a material absorbing/emitting a single dominant frequency, the heat flux and pressure diverge at small separations  d  as

red ball  Example of non-equilibrium Casimir levitation: M. Krüger, G .Bimonte, T. Emig, and M. Kardar, Phys. Rev. B 86, 115423 (2012)

yellow ball A hot micro-sphere can levitate on top of a cold plate: Falls down if it cools down (due to heat transfer),