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arXiv · hep-ph/0005236

Universal Torsion-Induced Interaction from Large Extra Dimensions

Abstract

We consider the Kaluza-Klein (KK) scenario in which only gravity exists in the bulk. Without the assumption of symmetric connection, the presence of brane fermions induces torsion. The result is a universal axial contact interaction that dominates those induced by KK gravitons. This enhancement arises from a large spin density on the brane. Using a global fit to Z-pole observables, we find the 3 sigma bound on the scale of quantum gravity to be 28 TeV for n=2. If Dirac or light sterile neutrinos are present, the data from SN1987A increase the bound to \sqrt{n}M_S >= 210 TeV.

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Lay Nam Chang, Oleg Lebedev, Will Loinaz, Tatsu Takeuchi. 2000-10-11. Universal Torsion-Induced Interaction from Large Extra Dimensions. https://doi.org/10.1103/physrevlett.85.3765

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