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arXiv · hep-th/9905137

Higher Loop Effects on Unification via Kaluza-Klein Thresholds

Zurab Kakushadze·Tomasz R. Taylor
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Abstract

We discuss higher loop corrections to gauge coupling renormalization in the context of gauge coupling unification via Kaluza-Klein thresholds. We show that in the case N=1 supersymmetric compactifications the one-loop threshold contributions are dominant, while the higher loop correction are subleading. This is due to the fact that at heavy Kaluza-Klein levels the spectrum as well as the interactions are N=2 supersymmetric. In particular, we give two different arguments leading to this result - one is field theoretic, while the second one utilizes the power of string perturbation techniques. To illustrate our discussions we perform explicit two-loop computations of various corrections to gauge couplings within this framework. We also remark on phenomenological applications of our discussions in the context of TeV-scale brane world.

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Zurab Kakushadze, Tomasz R. Taylor. 1999-09-08. Higher Loop Effects on Unification via Kaluza-Klein Thresholds. https://doi.org/10.1016/s0550-3213(99)00517-9

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