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arXiv · 1703.00791

Isotropic Lifshitz point in the O(N) Theory

Dario Zappala
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Abstract

The presence of an isotropic tricritical Lifshitz point for the O(N) scalar theory is investigated in the 1/N expansion by means of the Functional Renormalization Group equations. At leading order, the non-trivial Lifshitz point is observed if the number of dimensions d is taken between d=4 and d=8, and the eigenvalue spectrum of the associated eigendirections is derived. At order 1/N, the anomalous dimension eta_N is computed and it is found to vanish both in d=4 and d=8, while it turns out to be positive between these two values, although strongly dependent on the choice of infrared regulator.

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Dario Zappala. 2018-09-28. Isotropic Lifshitz point in the O(N) Theory. https://doi.org/10.1016/j.physletb.2017.08.051

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