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Roy-Steiner equations for gamma gamma -> pi pi

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 نشر من قبل Martin Hoferichter
 تاريخ النشر 2011
  مجال البحث
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Starting from hyperbolic dispersion relations, we derive a system of Roy--Steiner equations for pion Compton scattering that respects analyticity, unitarity, gauge invariance, and crossing symmetry. It thus maintains all symmetries of the underlying quantum field theory. To suppress the dependence of observables on high-energy input, we also consider once- and twice-subtract



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