arXiv subjects

Wen-Yu Wen

Publications and source records attributed to Wen-Yu Wen.

At least 19 recordsLinked to original sources

arXiv2026

Revisit Weak Cosmic Censorship in Einstein-Maxwell-Dilaton Black Holes: Third-order Protection, Swampland Distance Conjecture, and Weak Gravity Conjectures

We extend the earlier analysis of cosmic censorship and the Weak Gravity Conjecture (WGC) in Einstein--Maxwell-dilaton (EMD) theory by performing a complete higher-order Sorce--Wald gedankenexperiment on the static charged Gibbons--Maeda--Garfinkle--Horowitz--Strominger (GMG) black hole. In the probe limit, an extremal GMG black hole can apparently be overcharged by a test particle, seemingly violating the weak cosmic censorship conjecture (WCCC), which is nothing but first-order variational identity in the Iyer--Wald formalism. This window can be closed by either incorporating backreaction via the Hoop Conjecture or further including second-order variational identities. In this paper, we explicitly compute third-order variational identities. The extremality parameter eta remains non-negative to the third perturbative orders confirming WCCC protection, regardless of the apparent failure of all-order generalization, model-independent proof of Lu, et al.. We further incorporate the Swampland Distance Conjecture (SDC): the resulting infinite tower of light charged states discharges any would-be overcharged configuration on a timescale tau much less than 2M, exponentially faster than a horizon can be destroyed, reinforcing WCCC in dynamical regimes and strongly relaxing the original WGC charge-to-mass bound.

gr-qc↗

arXiv2026

Time-Crystalline Phase in a Single-Band Holographic Superconductor

We investigate the emergence of a time-crystalline phase in a single-band holographic superconductor, extending the AdS/CFT framework. By incorporating a nonlinear gauge-scalar coupling and external driving, we derive coupled equations of motion for the plasma and Higgs modes, analogous to those in high-Tc superconductors. Multi-scale analysis reveals a sum resonance with subharmonic growth indicating broken time-translation symmetry. We perform numerical computation of quasinormal mode and demonstrate the transition to the time-crystalline phase. The holographic model may serve as a robust tool for studying strongly coupled time crystals.

hep-th↗

arXiv2025

A Quantum Circuit Model of Black Hole Evaporation with Tunable Semi-Causality Violation

We present a four-qubit quantum circuit model of black hole evaporation with a controlled violation of semi-causality, understood as the condition that information may fall into the black hole but cannot propagate back across the horizon. Building on Broda's semi-causal evaporation circuit, we introduce a controlled-unitary gate $\mathrm{CU}(\sigma)$ that allows tunable information leakage from the interior to the exterior while preserving global unitarity. We compute the single-qubit reduced entropies, together with the mutual information and entanglement negativity for the BH-GR and IN-OUT bipartitions, at each discrete time step. For $\sigma=0$, the model reproduces Broda's Page-like entropy evolution with complete late-time purification. For any $\sigma>0$, however, nonzero residual single-qubit entropies and persistent late-time entanglement remain, indicating incomplete purification of the outgoing radiation despite the global unitary evolution. In the small-$\sigma$ regime, the residual entropy exhibits a characteristic $-\sigma^{2}\ln\sigma^{2}$ scaling that bears qualitative similarity to logarithmic entropy corrections in generalized uncertainty principle inspired evaporation scenarios. For larger values of $\sigma$, the persistence of finite residual entropy invites comparison with remnant-like endpoint configurations in regular or extremal black hole models. Our results show how controlled departures from the semi-causal limit modify information recovery in a minimal analytically tractable model of black hole evaporation.

hep-th↗

arXiv2024

A study of layered holographic superconductor

We have investigated a holographic model of a multi-layered superconductor in (2+1)-dimensions using the AdS/CFT correspondence. This correspondence allows us to study strongly interacting condensed matter systems through a weakly interacting gravitational theory. Our study focused on the effects of a finite system size on the superconductor's properties. We observed significant variations in the critical temperature and critical magnetic field depending on the number of layers and the spacing between them. Notably, our results capture the transition from a two-dimensional (2D) to a three-dimensional (3D) behavior in the limit of a large number of closely spaced layers. This transition signifies a change in how the superconductivity operates within real material.

hep-th↗

arXiv2023

Reflected entropy and Markov gap in non-inertial frames

We explore the reflected entropy and the Markov gap between two modes of a free fermionic field as observed by accelerating observers. This is done for both bipartite system which is described by Bell state and tripartite systems which are represented by Werner and Greenberger-Horne-Zeilinger states. The reflected entropy degrades monotonically as a result of the Unruh effect, eventually reaching a non-zero minimum value in the limit of infinite acceleration. Furthermore, we show that the Markov gap exhibits monotonic behavior with regard to acceleration in all three cases. In addition, we suggest a function for reflected entropy which decreases monotonically with decreasing Unruh temperature for all states. Finally, we confirm that the reflected entropy for our system does reduce under the partial tracing of the degrees of freedom for our states.

quant-ph↗

arXiv2022

Open String Probe in Soft Hair BTZ

We study the boundary CFT under supertranslation in terms of the AdS/CFT correspondence. In particular, we probe the soft hair BTZ background by several open string configurations as follows. The Ryu-Takayanaki formula of holographic entanglement remains intact under supertranslation. The U-shape string probe indicates that the flat part of meson potential is altered by the soft charge. The trailing string solution shows that the hair parameter plays the role of external field in the drag force. The study of hanging string in the Brownian motion suggests the transport variables, such as friction coefficient are likely affected by supertranslation.

hep-th↗

arXiv2022

Entanglement at the Soft-Hair Horizon

We study entanglement between two modes of a free bosonic and fermionic field as seen by two relatively accelerating observers at the soft-hair horizon of a four-dimensional supertranslated Schwarzschild black hole. First, we associate the shock wave to the near horizon geometry by explicit construction of map between their metric as well as relation between wave form factor and soft hair function. We then compute mutual information and entanglement negativity as a measure of entanglement between these two observers and show that their angular dependence at the soft-hair horizon. We also show that for vanishing soft hair function our results are equal to that of an ordinary Schwarzschild black hole case.

hep-th↗

arXiv2021

Dressed Tunneling in Soft Hair

We revisit the Parikh-Wilczek's tunneling model of Hawking radiation in the Schwarzschild black hole with soft hair. Unlike the no-hair black hole, tunneling through the degenerate event horizon generated by supertranslation hair picks up an angular dependence, which suggests a hairy modification to the Bekenstein-Hawking entropy. At last, we discuss several implications and possible observable of soft hair.

hep-th↗

arXiv2019

Spin chains and classical strings in two parameters $q$-deformed AdS$_3\times$S$^3$

In this paper, we study the spin chain and string excitation in the two-parameters $q$-deformed AdS$_3\times$S$^3$ proposed by Hoare. We obtain the deformed spin chain model at the fast spin limit for choices of deformed parameters. General ansatz for giant magnons are studied in great detail and complicated dispersion relation is treated perturbatively. We also study several types of hanging string solutions and their charges and spins are analyzed numerically. At last, we explore its pp-wave limit and find its solution only depends on the difference of deformed parameters.

hep-th↗

arXiv2019

Hawking Radiation As Stimulated Emission

We regard the Parikh-Wilczek's tunnelling model of Hawking radiation as a quantum mechanical process of stimulated emission. The hypothesized microstates are found at the horizon with double degeneracy. A Jaynes-Cummings toy model for a black hole in the cavity is proposed to demonstrate how to write a qubit via the angular-dependent transition coupling, which might be related to the soft Goldstone hairs at analytic continuation. At last, we show how information is retained in the black hole by computing the time evolution of mutual entanglement entropy in the cavity-black holes system.

hep-th↗

arXiv2018

Cosmic Censorship and Weak Gravity Conjecture in the Einstein-Maxwell-dilaton theory

We explore the cosmic censorship in the Einstein-Maxwell-dilaton theory following Wald's thought experiment to destroy a black hole by throwing in a test particle. We discover that at probe limit the extremal charged dilaton black hole could be destroyed by a test particle with specific energy. Nevertheless the censorship is well protected if backreaction or self-force is included. At the end, we discuss an interesting connection between Hoop Conjecture and Weak Gravity Conjecture.

gr-qc↗

arXiv2018

Charged rotating BTZ black holes in noncommutative spaces and torsion gravity

We consider charged rotating BTZ black holes in noncommutative space by use of Chern-Simons theory formulation of $2+1$ dimensional gravity. The noncommutativity between the radial and the angular variables is introduced through the Seiberg-Witten map for gauge fields, and the deformed geometry to the first order in the noncommutative parameter is derived. It is found that the deformation also induces nontrivial torsion, and the Einstein-Cartan theory appears to be a suitable framework to investigate the equations of motion. Though the deformation is indeed nontrivial, the deformed and the original Einstein equations are found to be related by a rather simple coordinate transformation.

hep-th↗

arXiv2017

Entropic uncertainty relation based on generalized uncertainty principle

We explore the modification of the entropic formulation of uncertainty principle in quantum mechanics which measures the incompatibility of measurements in terms of Shannon entropy. The deformation in question is the type so called generalized uncertainty principle that is motivated by thought experiments in quantum gravity and string theory and is characterized by a parameter of Planck scale. The corrections are evaluated for small deformation parameters by use of the Gaussian wave function and numerical calculation. As the generalized uncertainty principle has proven to be useful in the study of the quantum nature of black holes, this study would be a step toward introducing an information theory viewpoint to black hole physics.

hep-th↗

arXiv2017

Extremal noncommutative black holes as dark matter furnaces

In this letter, we consider dark matter annihilation in the gravitational field of noncommutative black holes. At final stage of evaporation, we hypothesize the existence of a thermal equilibrium state composed of a burning black hole relics fueled by dark matter accretion.

hep-th↗

arXiv2016

Finiteness of Entanglement Entropy in Quantum Black Hole

A logarithmic but divergent term usually appears in the computation of entanglement entropy circumferencing a black hole, while the leading quantum correction to the Bekenstein-Hawking entropy also takes the logarithmic form. A quench model of CFT within finite Euclidean time was proposed in the \cite{Kuwakino:2014nra} to regard this logarithmic term as entanglement between radiation and the black hole, and this proposal was justified by the alternative sign for $n$-partite quantum information. However, this preliminary form suffers from the notorious divergence at its low temperature limit. In this letter, we propose a modified form for black hole entanglement entropy such that the divergence sickness can be cured. We discuss the final stage of black hole due to this modification and its relation to R{è}nyi entropy, higher loop quantum correction and higher spin black holes.

hep-th↗

arXiv2016

Holographic Model of Dual Superconductor for Quark Confinement

We show that a hairy black hole solution can provide a holographically dual description of quark confinement. There exists a one-parameter sensible metric which receives the backreaction of matter contents in the holographic action, where the scalar and gauge field are responsible for the condensation of chromomagnetic monopoles. This model features a preconfining phase triggered by second-order monopole condensation and a first-order confinement/deconfinement phase transition. To confirm the confinement, the quark-antiquark potential is calculated by probing a QCD string in both phases. At last, contribution from Kaluza-Klein monopoles in the confining phase is discussed.

hep-th↗

arXiv2016

Classical and Quantum Szilard Engine under Generalized Uncertainty Principle Effect

We studied the Szilard engine under the effect of generalized uncertainty principle (GUP). In the classical Szilard engine, the work done by the engine is reduced by the GUP effect via a modified ideal gas law. In the quantum Szilard engine, the correction comes from the shifted eigen energy due to the nonlinear momentum dependence. We studied its effect on both bosonic and fermionic molecules.

hep-th↗

arXiv2016

Offshell thermodynamic metrics of the Schwarzschild black hole

Thermodynamic metric usually works only for those black holes with more than one conserved charge, therefore the Schwarzschild black hole was excluded. In this letter, we compute and compare different versions of offshell thermodynamic metric for the Schwarzschild-like black hole by introducing a new degree of freedom. This new degree of freedom could be the running Newton constant, a cutoff scale for regular black hole, a noncommutative deformation, or the deformed parameter in the nonextensive Tsallis-Renyi entropy. The onshell metric of the deformed Schwarzschild solution would correspond to the submanifold by gauge fixing of this additional degree of freedom. In particular, the thermal Ricci scalar for the Schwarzschild black hole, though different for various deformation, could be obtained by switching off the deformation.

gr-qc↗