
Light can scatter from light, CERN physicists confirm - wwarner
https://physicsworld.com/a/light-can-scatter-from-light-cern-physicists-confirm/
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wwarner
I don't understand the physics here... photons are bosons, and bosons pass
through each other. Is the idea that the photons passing through the
fluctuating vacuum occasionally produce fermions that can bump into each
other, and then when they recombine the trajectory of the photons has changed?

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Iolaum
The relevant physics for photon-photon scattering is Quantum Electrodynamics
and is elegantly described by Feynman Diagrams. See the relevant diagrams on
this stack exchange question:
[https://physics.stackexchange.com/questions/215697/photon-
ph...](https://physics.stackexchange.com/questions/215697/photon-photon-
scattering-feynman-diagram)

To make a crude description, virtual fermions are exchanged between the two
photons and this results in transfer of momentum and energy between them.

