Partition functions and entanglement entropy: Weyl graviton and conformal higher spin fields

We consider an antisymmetric gauge field in the Minkowski space of d-dimension and decompose it in terms of the antisymmetric tensor harmonics and fix the gauge. The Gauss law implies that the normal component of the field strength on the spherical entangling surface will label the superselection sectors. From the two-point function of the field strength on the sphere, we evaluate the logarithmic divergent term of the entanglement entropy of edge modes of p-form field. We observe that the logarithmic divergent term in entanglement entropy of edge modes coincides with the edge partition function of co-exact p-form on the sphere when expressed in terms of the Harish-Chandra characters. We also develop a boundary path integral of the antisymmetric p-form gauge field. From the boundary path integral, we show that the edge mode partition function corresponds to the co-exact (p − 1)-forms on the boundary. This boundary path integral agrees with the direct evaluation of the entanglement entropy of edge modes extracted from the two-point function of the normal component of the field strength on the entangling surface.

Section: Discussionmentioning

confidence: 77%

Entanglement entropy and the boundary action of edge modes

Mukherjee

2024

“…It will be nice to develop the HKLL procedure for higher derivative conformal fields and conformal higher spin fields. These theories provide essential tools to study conformal field theories in higher dimensions, including free energies and conformal anomalies [37,38,39,40]. However, these theories are non-unitary in general due to the presence of higher derivatives in the kinetic term in the action.…”

Section: Discussionmentioning

confidence: 99%

HKLL for the non-normalizable mode

Bhattacharjee

Krishnan

Sarkar

2022

We discuss various aspects of HKLL bulk reconstruction for the free scalar field in AdSd+1. First, we consider the spacelike reconstruction kernel for the non-normalizable mode in global coordinates. We construct it as a mode sum. In even bulk dimensions, this can be reproduced using a chordal Green’s function approach that we propose. This puts the global AdS results for the non-normalizable mode on an equal footing with results in the literature for the normalizable mode. In Poincaré AdS, we present explicit mode sum results in general even and odd dimensions for both normalizable and non-normalizable kernels. For generic scaling dimension ∆, these can be re-written in a form that matches with the global AdS results via an antipodal mapping, plus a remainder. We are not aware of a general argument in the literature for dropping these remainder terms, but we note that a slight complexification of a boundary spatial coordinate (which we call an iϵ prescription) allows us to do so in cases where ∆ is (half-) integer. Since the non-normalizable mode turns on a source in the CFT, our primary motivation for considering it is as a step towards understanding linear wave equations in general spacetimes from a holographic perspective. But when the scaling dimension ∆ is in the Breitenlohner-Freedman window, we note that the construction has some interesting features within AdS/CFT.

“…But Wick rotating the Euclidean time to real-time should lead to the analysis of the local quench by the fermionic operators [21]. Another important direction would be to understand pseudoentropy in conformal higher derivative and conformal higher spin fields [25,26] where one has to develop two and four-point functions on the replica surface. It will be nice to show the non-unitarity nature of these theories within the framework of pseudo entropy.…”

Section: Jhep10(2022)016mentioning

confidence: 99%

Pseudo Entropy in U(1) gauge theory

Mukherjee

2022

Self Cite

We study the properties of pseudo entropy, a new generalization of entanglement entropy, in free Maxwell field theory in d = 4 dimension. We prepare excited states by the different components of the field strengths located at different Euclidean times acting on the vacuum. We compute the difference between the pseudo Rényi entropy and the Rényi entropy of the ground state and observe that the difference changes significantly near the boundary of the subsystems and vanishes far away from the boundary. Near the boundary of the subsystems, the difference between pseudo Rényi entropy and Rényi entropy of the ground state depends on the ratio of the two Euclidean times where the operators are kept. To begin with, we develop the method to evaluate pseudo entropy of conformal scalar field in d = 4 dimension. We prepare two states by two operators with fixed conformal weight acting on the vacuum and observe that the difference between pseudo Rényi entropy and ground state Rényi entropy changes only near the boundary of the subsystems. We also show that a suitable analytical continuation of pseudo Rényi entropy leads to the evaluation of real-time evolution of Rényi entropy during quenches.