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arXiv · 1808.07697

Fermion bilinear operator critical exponents at $O(1/N^2)$ in the QED-Gross-Neveu universality class

J. A. Gracey
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Abstract

We use the critical point large $N$ formalism to calculate the critical exponents corresponding to the fermion mass operator and flavour non-singlet fermion bilinear operator in the universality class of Quantum Electrodynamics (QED) coupled to the Gross-Neveu model for an $SU(N)$ flavour symmetry in $d$-dimensions. The $ε$ expansion of the exponents in $d$ $=$ $4$ $-$ $2ε$ dimensions are in agreement with recent three and four loop perturbative evaluations of both renormalization group functions of these operators. Estimates of the value of the non-singlet operator exponent in three dimensions are provided.

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J. A. Gracey. 2018-09-20. Fermion bilinear operator critical exponents at $O(1/N^2)$ in the QED-Gross-Neveu universality class. https://doi.org/10.1103/physrevd.98.085012

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