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General scalar renormalisation group equations at three-loop order

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 نشر من قبل Tom Steudtner
 تاريخ النشر 2020
  مجال البحث
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 تأليف Tom Steudtner




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For arbitrary scalar QFTs in four dimensions, renormalisation group equations of quartic and cubic interactions, mass terms, as well as field anomalous dimensions are computed at three-loop order in the $overline{text{MS}}$ scheme. Utilising pre-existing literature expressions for a specific model, loop integrals are avoided and templates for general theories are obtained. We reiterate known four-loop expressions, and derive $beta$ functions for scalar masses and cubic interactions from it. As an example, the results are applied to compute all renormalisation group equations in $U(n) times U(n)$ scalar theories.



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