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arXiv · 0902.0364

Universal properties of the U(1) current at deconfined quantum critical points: comparison with predictions from gauge/gravity duality

Flavio S. Nogueira
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Abstract

The deconfined quantum critical point of a two-dimensional SU(N) antiferromagnet is governed by an Abelian Higgs model in $d=2+1$ spacetime dimensions featuring $N$ complex scalar fields. In this context, we derive for $2\leq d\leq 4$ an exact formula for the central charge of the U(1) current in terms of the gauge coupling at quantum criticality and compare it with the corresponding result obtained using gauge-gravity duality. There is a remarkable similarity precisely for $d=2+1$. In this case the amplitude of the current correlation function has the same form as predicted by the gauge-gravity duality. We also compare finite temperature results for the charge susceptibility in the large $N$ limit with the result predicted by the gauge-gravity duality. Our results suggest that condensed matter systems at quantum criticality may provide interesting quantitative tests of the gauge-gravity duality even in absence of supersymmetry.

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Flavio S. Nogueira. 2009-04-27. Universal properties of the U(1) current at deconfined quantum critical points: comparison with predictions from gauge/gravity duality. https://doi.org/10.1103/physrevd.79.105007

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