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Updated: Jun 5, 2026

Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
Sum rules for light-by-light scattering
Vladimir Pascalutsa1, Marc Vanderhaeghen
1Institut für Kernphysik, Johannes Gutenberg Universität, Mainz D-55099, Germany.
Abstract:
We derive a set of sum rules for the light-by-light scattering and fusion: γγ→all, and verify them in lowest order QED calculations. A prominent implication of these sum rules is the superconvergence of the helicity-difference total cross section for photon fusion, which in the hadron sector reveals an intricate cancellation between the pseudoscalar and tensor mesons. An experimental verification of superconvergence of the polarized photon fusion into hadrons is called for, but will only be possible at e+ e- and γγ colliders with both beams polarized. We also show how the sum rules can be used to measure various contributions to the low-energy light-by-light scattering.
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