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Holographic R磂nyi entropy for two-dimensional N=(2,2) superconformal field theory

Zhibin Li; Jia-ju ZhangSubjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc.

We investigate the holographic R?enyi entropy for two-dimensional N = (2, 2) superconformal field theory (SCFT), which is dual to N = 2 supergravity in AdS3 background. In SCFT we have the stress tensor,current, and their supersymmetric partners, and in supergravity we have the graviton, vector field, and two gravitinos. We get the R?enyi mutual information of two short intervals on complex plane in expansion by the cross ratio x to order x4, and R?enyi entropy of one interval on torus in expansion by q = exp(?2 /L), with being the inverse temperature and L being the spatial period, to order q2. We calculate in both the supergravity and SCFT sides, and find matches of the results. |

Novel BPS Wilson loops in three-dimensional quiver Chern–Simons-matter theories

Hao Ouyang; Jun-Bao Wu; Jia-ju ZhangSubjects: Physics >> Nuclear Physics

We show that generic three-dimensional燦=2爍uiver super Chern-Simons-matter theories admit Bogomol'nyi-Prasad-Sommerfield (BPS) Drukker-Trancanelli (DT) type Wilson loops. We investigate both Wilson loops along timelike infinite straight lines in Minkowski spacetime and circular Wilson loops in Euclidean space. In Aharnoy-Bergman-Jafferis-Maldacena theory, we find that generic BPS DT type Wilson loops preserve the same number of supersymmetries as Gaiotto-Yin type Wilson loops. There are several free parameters for generic BPS DT type Wilson loops in the construction, and supersymmetry enhancement for Wilson loops happens for special values of the parameters. |

Subjects: Physics >> Nuclear Physics

In this paper we investigate the holographic R\'enyi entropy in N=1 supergravity (SUGRA) in AdS3 spacetime, which is dual to the two-dimensional N=(1,1) superconformal field theory (SCFT). We consider both cases of two short intervals on a line with zero temperature and one interval on a circle with low temperature. In SUGRA side we consider contributions of both graviton and gravitino, and in SCFT side we consider contributions of both stress tensor T, ?T and their superpartners G, ?G We find matches between SUGRA and SCFT results. |

Supersymmetric Wilson loops in $ \mathcal{N}=4 $ super Chern-Simons-matter theory

Hao Ouyang; Jun-Bao Wu; Jia-ju ZhangSubjects: Physics >> Nuclear Physics

We investigate the supersymmetric Wilson loops in?d=3?N=4?super Chern-Simons-matter theory obtained from non-chiral orbifold of ABJM theory. We work in both Minkowski spacetime and Euclidean space, and we construct 1/4 and 1/2 BPS Wilson loops. We also provide a complete proof that the difference between 1/4 and 1/2 Wilson loops is?Q-exact with?Q?being some supercharge that is preserved by both the 1/4 and 1/2 Wilson loops. This plays an important role in applying the localization techniques to compute the vacuum expectation values of Wilson loops. We also study the M-theory dual of the 1/2 BPS circular Wilson loop. |

BPS Wilson loops in Minkowski spacetime and Euclidean space

Hao Ouyang; Jun-Bao Wu; Jia-ju ZhangSubjects: Physics >> Nuclear Physics

We give evidence that spacelike BPS Wilson loops do not exist in Minkowski spacetime. We show that spacelike Wilson loops in Minkowski spacetime cannot preserve any supersymmetries, in d = 4 N = 4 super Yang-Mills theory,d = 3 N = 2 super Chern-Simons-matter theory, and d = 3 N = 6 Aharony-Bergman-Jafferis-Maldacena theory. We not only show this using infinite straight lines and circles as examples, but also we give proofs for general curves. We attribute this to the conflicts of reality conditions of the spinors. However, spacelike Wilson loops do exist in Euclidean space. There are both BPS Wilson loops along infinite straight lines and circular BPS Wilson loops. This is because the reality conditions of the spinors are lost after Wick rotation. The result is reasonable in view of the AdS/CFT correspondence. |

Short interval expansion of R\'enyi entropy on torus

Bin Chen; Jun-Bao Wu; Jia-ju ZhangSubjects: Physics >> Nuclear Physics

We investigate the short interval expansion of the R\'enyi entropy for two-dimensional conformal field theory (CFT) on a torus. We require the length of the interval???to be small with respect to the spatial and temporal sizes of the torus. The operator product expansion of the twist operators allows us to compute the short interval expansion of the R\'enyi entropy at any temperature. In particular, we pay special attention to the large?c?CFTs dual to the AdS3?gravity and its cousins. At both low and high temperature limits, we read the R\'enyi entropies to order??6, and find good agreements with holographic results. Moreover, the expansion allows us to read?1/c?contribution, which is hard to get by expanding the thermal density matrix. We generalize the study to the case with the chemical potential as well. |

On one-loop entanglement entropy of two short intervals from OPE of twist operators

Zhibin Li; Jia-ju ZhangSubjects: Physics >> Nuclear Physics

We investigate the one-loop entanglement entropy of two short intervals with small cross ratio?x?on a complex plane in two-dimensional conformal field theory (CFT) using operator product expansion of twist operators. We focus on the one-loop entanglement entropy instead of the general order?n?R\'enyi entropy, and this makes the calculation much easier. We consider the contributions of stress tensor to order?x10, contributions of?W3?operator to order?x12, and contributions of?W4?operator to order?x14. The CFT results agree with the ones in gravity. |

[1 Pages/ 7 Totals]