Thermodynamical property of entanglement entropy and deconfinement phase transition

We analyze the holographic entanglement entropy in a soliton background with Wilson lines and derive a relation analogous to the first law of thermodynamics. The confinement/deconfinement phase transition occurs due to the competition of two minimal surfaces. The entropic c function probes the confinement/deconfinement phase transition. It is sensitive to the degrees of freedom (DOF) smaller than the size of a spatial circle. When the Wilson line becomes large, the entropic c function becomes non-monotonic as a function of the size and does not satisfy the usual c-theorem. We analyze the entanglement entropy for a small subregion and the relation analogous to the first law of thermodynamics. For the small amount of Wilson lines, the excited amount of the entanglement entropy decreases from the ground state. It reflects that confinement decreases degrees of freedom. We finally discuss the second order correction of the holographic entanglement entropy.Comment: 25 pages, 5 figures; v2 minor changes, references adde

The Tensor Current Divergence Equation in U(1) Gauge Theories is Free of Anomalies

The possible anomaly of the tensor current divergence equation in U(1) gauge theories is calculated by means of perturbative method. It is found that the tensor current divergence equation is free of anomalies.Comment: Revtex4, 7 pages, 2 figure

A systematic approach to correlators in TTˉT\bar{T} deformed CFTs

We investigate higher-order corrections to correlators in a general CFT with the double trace $T\bar{T}$ deformation. Traditional perturbation theory proves inadequate for addressing this issue, due to the intricate stress tensor flow induced by the deformation. To tackle this challenge, we introduce a novel technique termed the conservation equation method. This method leverages the trace relation and conservation property of the stress tensor to establish relationships between higher and lower-order corrections and subsequently determine the correlators by enforcing symmetry properties. As an illustration, we compute both first and higher-order corrections, demonstrating the impact of stress tensor deformation on correlators in a general deformed CFT. Our results align with existing calculations in the literature.Comment: 17+12 pages, 1 figur

Efficient, low-cost techniques to verify carrier aggregation in mobile devices

Carrier aggregation (CA) is a key feature of recent wireless standards (4G, 5G, NR, etc.) that enables combining of two or more carriers into a single data channel to increase capacity. The number of carrier combinations can be very large, and verifying all combinations, or even a representative fraction thereof, involves a time-consuming and expensive commitment of engineering resources and test equipment. Per the techniques described herein, for time-division duplex standards, a first mobile device under test (DUT) is verified for CA operation by a second DUT. For example, a transmit CA combination of a first DUT is verified by the proper detection of the CA combination by a second DUT. The techniques simplify CA testing and reduce verification/compliance costs

The Entanglement in Anisotropic Heisenberg XYZ Chain with inhomogeneous magnetic field

The thermal entanglement of a two-qubit anisotropic Heisenberg $XYZ$ chain under an inhomogeneous magnetic field b is studied. It is shown that when inhomogeneity is increased to certain value, the entanglement can exhibit a larger revival than that of less values of b. The property is both true for zero temperature and a finite temperature. The results also show that the entanglement and critical temperature can be increased by increasing inhomogeneous exteral magnetic field

A Note on Transverse Axial Vector and Vector Anomalies in U(1) Gauge Theories

The transverse axial vector and vector anomalies in four-dimensional U(1) gauge theories studied in [10] is reexamined by means of perturbative methods. The absence of transverse anomalies for both axial vector and vector current is verified. We also show that the Pauli-Villars regularization and dimensional regularization give the same result on the transverse anomaly of both axial vector and vector current.Comment: Revtex4, 8 pages, two figures. Largely revised, using the Pauli-Villars regularization instead of dimensional regularization in the main proof. Final form to be published in Physics Letters