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Conformal 3-point functions and the Lorentzian OPE in momentum space

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 نشر من قبل Marc Gillioz
 تاريخ النشر 2019
  مجال البحث
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 تأليف Marc Gillioz




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In conformal field theory in Minkowski momentum space, the 3-point correlation functions of local operators are completely fixed by symmetry. Using Ward identities together with the existence of a Lorentzian operator product expansion (OPE), we show that the Wightman function of three scalar operators is a double hypergeometric series of the Appell $F_4$ type. We extend this simple closed-form expression to the case of two scalar operators and one traceless symmetric tensor with arbitrary spin. Time-ordered and partially-time-ordered products are constructed in a similar fashion and their relation with the Wightman function is discussed.



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