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Background Field Method and Generalized Field Redefinitions in Effective Field Theories

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 نشر من قبل Andrea Quadri
 تاريخ النشر 2021
  مجال البحث
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 تأليف Andrea Quadri




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We show that in a spontaneously broken effective gauge field theory, quantized in a general background $R_xi$-gauge, also the background fields undergo a non-linear (albeit background-gauge invariant) field redefinition induced by radiative corrections. This redefinition proves to be crucial in order to renormalize the coupling constants of gauge-invariant operators in a gauge-independent way. The classical background-quantum splitting is also in general non-linearly deformed (in a non gauge-invariant way) by radiative corrections. Remarkably, such deformations vanish in the Landau gauge, to all orders in the loop expansion.



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