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arXiv · 1804.07801

Universality hypothesis breakdown at one-loop order

P. R. S. Carvalho
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Abstract

We probe the universality hypothesis by analytically computing, at least, the two-loop corrections to the critical exponents for $q$-deformed O($N$) self-interacting $\lambda\phi^{4}$ scalar field theories through six distinct and independent field-theoretic renormalization group methods and $\epsilon$-expansion techniques. We show that the effect of $q$-deformation on the one-loop corrections to the $q$-deformed critical exponents is null, so universality hypothesis is broken down at this loop order. Such effect emerges just, at least, at two-loop level and the validity of universality hypothesis is restored. The $q$-deformed critical exponents obtained through the six methods are the same and, furthermore, reduce to their non-deformed values in the appropriated limit.

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P. R. S. Carvalho. 2018-04-20. Universality hypothesis breakdown at one-loop order. https://doi.org/10.1103/physrevd.97.105006

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