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Constraining noncommutative field theories with holography

An important window to quantum gravity phenomena in low energy noncommutative (NC) quantum field theories (QFTs) gets represented by a specific form of UV/IR mixing. Yet another important window to quantum gravity, a holography, manifests itself in effective QFTs as a distinct UV/IR connection. In matching these two principles, a useful relationship connecting the UV cutoff $Λ_{\rm UV}$, the IR cutoff $Λ_{\rm IR}$ and the scale of noncommutativity $Λ_{\rm NC}$, can be obtained. We show that an effective QFT endowed with both principles may not be capable to fit disparate experimental bounds simultaneously, like the muon $g-2$ and the masslessness of the photon. Also, the constraints from the muon $g-2$ preclude any possibility to observe the birefringence of the vacuum coming from objects at cosmological distances. On the other hand, in NC theories without the UV completion, where the perturbative aspect of the theory (obtained by truncating a power series in $ Λ_{\rm NC}^{-2}$) becomes important, a heuristic estimate of the region where the perturbative expansion is well-defined $E/ Λ_{\rm NC} \lesssim 1$, gets affected when holography is applied by providing the energy of the system $E$ a $Λ_{\rm NC}$-dependent lower limit. This may affect models which try to infer the scale $Λ_{\rm NC}$ by using data from low-energy experiments.