Contactless friction
Friction at finite temperature, for stationary (time invariant) moving states:
"Shearing the vacuum - quantum friction," J.B. Pendry, J. Phys.: Condens. Matter 9, 10301 (1997).
"Near-field radiative heat transfer and non-contact friction," Volokitin & Persson, Rev. Mod. Phys. 79, 1291 (2007).
Friction at zero temperature, for accelerating bodies in vacuum, with accompanied emitted radiation.
"Quantum theory of the EM Field in a Variable-Length 1d cavity," G.T. Moore, J. Math. Phys. 11, 2679 (1970)
"Radiation from a moving mirror in 2d space-time," Fulling & Davies, Proc.R.Soc, Ser. A 348, 393 (1976).
Yakov Zel'dovich, "Generation of waves by a rotating body," JETP Lett. 14, 180 (1971), superradiant amplification
h
Consider waves of frequency 
and quantized angular momentum 
impinging on object rotation with frequency 
External reference frame variation of the fields: 
Object reference frame variation of the fields: 
If 
and have opposite signs:
Amplitude of (classical) scattered wave exceeds incoming wave (Super-radiance).
Conjectured (quantum) spontaneous emission with no incoming wave.
"Spontaneous emission by rotating objects: A scattering approach," Maghrebi, Jaffe & MK, PRL108, 230403 (2012).
Number of photons in a mode of frequency and angular momentum ,
generated by object rotating with angular velocity is:
E.g., net power for a rotating cylinder: 
Experimental verification of superradiance:
"Amplification of EM waves by a rotating body, M.C. Braidotti et al, Nature Communications 15:5453 1-6 (2024)
Future application?