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QEDs in $2{+}1$ dimensions: complex fixed points and dualities

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 نشر من قبل Hrachya Khachatryan
 تاريخ النشر 2018
  مجال البحث فيزياء
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We consider Quantum Electrodynamics with an even number $N_f$ of bosonic or fermionic flavors, allowing for interactions respecting at least $U(N_f/2)^2$ global symmetry. Both in the bosonic and in the fermionic case, we find four interacting fixed points: two with $U(N_f/2)^2$ symmetry, two with $U(N_f)$ symmetry. Large $N_f$ arguments suggest that, lowering $N_f$, all these fixed points merge pairwise and become complex CFTs. In the bosonic QEDs the merging happens around $N_fsim 9{-}11$ and does not break the global symmetry. In the fermionic QEDs the merging happens around $N_fsim3{-}7$ and breaks $U(N_f)$ to $U(N_f/2)^2$. When $N_f=2$, we show that all four bosonic fixed points are one-to-one dual to the fermionic fixed points. The merging pattern suggested at large $N_f$ is consistent with the four $N_f=2$ boson $lra$ fermion dualities, providing support to the validity of the scenario.



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