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arXiv · 1204.2246

On higher-order corrections in a four-fermion Lifshitz model

Abstract

We study a flavour-violating four-fermion interaction in the Lifshitz context, in 3+1 dimensions and with a critical exponent z=3. This model is renormalizable, and features dynamical mass generation, as well as asymptotic freedom. At one-loop, it is only logarithmically divergent, but the superficial degree of divergence of the two-point functions is 3. We calculate the two-loop corrections to the propagators, and show that, at this order, the Lorentz-violating corrections to the IR dispersion relation are quadratic in the cut off. Furthermore, these corrections are too important to represent a physical effect. As a consequence, the predictive power of the model in terms of Lorentz-violating effects in the propagation of particles is limited.

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J. Alexandre, J. Brister, N. Houston. 2013-03-08. On higher-order corrections in a four-fermion Lifshitz model. https://doi.org/10.1103/physrevd.86.025030

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