Dynamic Casimir Phenomena

red ball Accelerating bodies in vacuum may experience friction, and emit radiation.

yellow ball "Quantum Theory of the Electromagnetic Field in a Variable-Length One-Dimensional Cavity,"

G. T. Moore, J. Math. Phys. 11, 2679 (1970)

yellow ball "Radiation from a Moving Mirror in Two Dimensional Space-Time: Conformal Anomaly,"

S. A. Fulling and P. C. W. Davies, Proc. R. Soc. London, Ser. A 348, 393 (1976).


yellow ball "Observation of the dynamical Casimir effect in a superconducting circuit,"

C.M. Wilson, G. Johansson, A. Pourkabirian, M. Simoen, J.R. Johansson, T. Duty, F. Nori & P. Delsing, Nature 479, 376 (2011).

red ball Stationary (time invariant) moving states:

yellow ball "Shearing the vacuum - quantum friction,"

J.B. Pendry, J. Phys.: Condens. Matter 9, 10301 (1997).

yellow ball "Near-field radiative heat transfer and noncontact friction,"

A. I. Volokitin and B. N. J. Persson, Rev. Mod. Phys. 79, 1291 (2007).

red ballRotation: Consider waves of frequency ω and angular state m impinging on object rotating with frequency Ω

Lab frame:             

Object frame:         

yellow ball "Generation of waves by a rotating body,"

Ya B. Zel'dovich, JETP Lett. 14, 180 (1971);  If  ω' and  ω have opposite signs:

 yellow ball  Amplitude of (classical) scattered wave exceeds incoming wave (Super-radiance).

 yellow ball  Conjectured (quantum) spontaneous emission with no incoming wave.

yellow ball "Spontaneous emission by rotating objects: A scattering approach,"

M.F. Maghrebi, R.L. Jaffe, & M. Kardar, PRL108, 230403 (2012). 

yellow ballNumber of photons in a mode of frequency ω and angular momentum m,

generated by object rotating with angular velocity Ω  is:


yellow ballE.g., net power for a rotating cylinder:  

yellow ballThe rotating cylinder also drags and spins small test bodies in its vicinity.