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arXiv:1610.06568 · Physical review. B./Physical review. B

Entanglement entropy of large- N Wilson-Fisher conformal field theory

Seth Whitsitt, William Witczak‐Krempa, Subir Sachdev A

Published Jan 30, 2017• 51 citations
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Abstract

We compute the entanglement entropy of the Wilson-Fisher conformal field theory (CFT) in 2+1 dimensions with $\mathrm{O}(N)$ symmetry in the limit of large $N$ for general entanglement geometries. We show that the leading large-$N$ result can be obtained from the entanglement entropy of $N$ Gaussian scalar fields with their mass determined by the geometry. For a few geometries, the universal part of the entanglement entropy of the Wilson-Fisher CFT equals that of a CFT of $N$ massless scalar fields. However, in most cases, these CFTs have a distinct universal entanglement entropy even at $N=\ensuremath{\infty}$. Notably, for a semi-infinite cylindrical region it scales as ${N}^{0}$ in the Wilson-Fisher theory, in stark contrast to the $N$-linear result of the Gaussian fixed point.

DOI
10.1103/physrevb.95.045148

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