Universal corrections to entanglement entropy of local quantum quenches

作者：David Justin R^*; Khetrapal Surbhi; Kumar S Prem

来源：The Journal of High Energy Physics, 2016, 2016(8): 127.

DOI：10.1007/JHEP08(2016)127

• Field Theories in Lower Dimensions
• AdS-CFT Correspondence
• Higher Spin Symmetry

We study the time evolution of single interval Renyi and entanglement entropies following local quantum quenches in two dimensional conformal field theories at finite temperature for which the locally excited states have a finite temporal width epsilon. We show that, for local quenches produced by the action of a conformal primary field, the time dependence of Renyi and entanglement entropies at order epsilon(2) is universal. It is determined by the expectation value of the stress tensor in the replica geometry and proportional to the conformal dimension of the primary field generating the local excitation. We also show that in CFTs with a gravity dual, the epsilon(2) correction to the holographic entanglement entropy following a local quench precisely agrees with the CFT prediction. We then consider CFTs admitting a higher spin symmetry and turn on a higher spin chemical potential mu. We calculate the time dependence of the order epsilon(2) correction to the entanglement entropy for small mu, and show that the contribution at order epsilon(2) is universal. We verify our arguments against exact results for minimal models and the free fermion theory.

• 出版日期2016-8-22