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The Kallen-Lehmann representation for Lorentz-violating field theory

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 نشر من قبل Robertus Potting
 تاريخ النشر 2011
  مجال البحث
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 تأليف Robertus Potting




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We consider field-theoretic models, one consisting purely of scalars, the other also involving fermions, that couple to a set of constant background coupling coefficients transforming as a symmetric observer Lorentz two-tensor. We show that the exact propagators can be cast in the form of a Kallen-Lehmann representation. We work out the resulting form of the Feynman propagators and the equal-time field commutators, and derive sum rules for the spectral density functions.



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