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On the Lorentz-invariance of the Dyson series in theories with derivative couplings

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 نشر من قبل Alessandro Papa
 تاريخ النشر 2020
  مجال البحث
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We speculate on Dyson series for the $S$-matrix when the interaction depends on derivatives of the fields. We stick on two particular examples: the scalar electrodynamics and the renormalised $phi ^4$ theory. We eventually give evidence that Lorentz invariance is satisfied and that usual Feynman rules can be applied to the interaction Lagrangian.


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