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A comment on Atlas observes light scattering off light. Parent comment
"Light-by-light scattering is a very rare phenomenon in which two photons – particles of light – interact, producing again a pair of photons."
This is the process that they observe (for the first time) whereas E144 observed the Breit-Wheeler process.
You can argue that this is too narrow a definition of light-by-light scattering but they have at least tried to make it self consistent...
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"Light-by-light scattering is a very rare phenomenon in which two photons – particles of light – interact, producing again a pair of photons."
This is the process that they observe (for the first time) whereas E144 observed the Breit-Wheeler process.
You can argue that this is too narrow a definition of light-by-light scattering but they have at least tried to make it self consistent...