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arXiv · 1506.06616

$\epsilon$-Expansions Near Three Dimensions from Conformal Field Theory

Pallab Basu·Chethan Krishnan
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Abstract

We formally extend the CFT techniques introduced in arXiv:1505.00963, to $\phi^{\frac{2d_0}{d_0-2}}$ theory in $d=d_0-\epsilon$ dimensions and use it to compute anomalous dimensions near $d_0=3, 4$ in a unified manner. We also do a similar analysis of the $O(N)$ model in three dimensions by developing a recursive combinatorial approach for OPE contractions. Our results match precisely with low loop perturbative computations. Finally, using 3-point correlators in the CFT, we comment on why the $\phi^3$ theory in $d_0=6$ is qualitatively different.

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Pallab Basu, Chethan Krishnan. 2015-06-22. $\epsilon$-Expansions Near Three Dimensions from Conformal Field Theory. https://arxiv.org/abs/1506.06616

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