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arXiv · hep-ph/0404247

Collective polarization exchanges in collisions of photon clouds

R. F. Sawyer
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Abstract

The one-loop "vacuum" Heisenberg-Euler coupling of four electromagnetic fields can lead to interesting collective effects in the collision of two photon clouds, on a time scale orders of magnitude faster than one estimates from the cross-section and density. We estimate the characteristic time for macroscopic transformation of positive to negative helicity in clouds that are initially totally polarized and for depolarization of a polarized beam traversing an unpolarized cloud.

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R. F. Sawyer. 2004-07-23. Collective polarization exchanges in collisions of photon clouds. https://doi.org/10.1103/physrevlett.93.133601

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