arXiv subjects

Zi-Hao Li

Publications and source records attributed to Zi-Hao Li.

5 recordsLinked to original sources

arXiv2026

Constraints on Kasner Exponents from Holography and Energy Conditions

A central question in bottom-up holography is whether a given bulk effective theory admits a consistent holographic dual. In this work, we explore whether the near-singularity Kasner scaling of planar AdS black hole interiors can serve as a useful diagnostic based on interior-sensitive holographic probes. By examining the metric combinations that control interior-sensitive observables, including Complexity=Volume (CV), the bulk contribution to Complexity=Action (CA), Hartman-Maldacena (HM) entropy, and the thermal $a$-function, we derive algebraic bounds on the Kasner exponents $(p_t,p_s)$ for the relevant semi-classical regimes: finite-radius late-time branches of CV and HM, finite CA complexity, and a finite near-singularity thermal $a$-function. The resulting inequalities delineate the corresponding regions of Kasner space in which the terminal scaling alone is sufficient to realize these behaviors. Furthermore, we demonstrate that classical energy conditions, specifically the null and dominant energy conditions, provide simple sufficient criteria ensuring that the Kasner exponents fall within these holographically allowed regions. These results establish a direct connection between classical bulk energy conditions and the interior geometry selected by holographic probes, and suggest that Kasner scaling can provide a complementary diagnostic in bottom-up holography.

hep-th↗

arXiv2026

Linear Growth of Holographic Time-like Entanglement Entropy and Kasner exponents

The holographic time-like entanglement entropy (TEE) extends entanglement to time-like boundary subregions. While its definitive holographic dictionary remains debated, one concrete proposal utilizes piece-wise extremal surfaces. In this work, we adopt this geometric prescription as an exploratory framework to holographically investigate the late-time ($τ_0\to \infty$) growth of TEE in asymptotically AdS black holes with a space-like singularity and no inner horizon. By assuming a Kasner geometry near the space-like singularity and using the null energy condition, we analytically show that a critical extremal surface $\mathcal{A}_c$ inside the event horizon completely governs the late-time linear growth of the TEE. This result suggests that the late-time behavior of TEE is tightly constrained by the geometry of black hole interiors. While the dominant energy condition (DEC) guarantees an upper bound for the real part's growth rate, we conjecture a corresponding universal lower bound for the imaginary part. Numerical results from Einstein-scalar theory demonstrate the robustness of this bounding behavior: the vacuum Schwarzschild-AdS geometry consistently maximizes the real growth rate and minimizes the imaginary part, suggesting these bounds hold in broader holographic setups.

hep-th↗

arXiv2026

Purcell effect and quantum Zeno effect suppressed self-discharging of quantum battery

Quantum batteries (QB), as an energy storage and transfer device, not only show obvious advantages compared to classical electrochemical batteries, but also have important applications in quantum information. Self-discharging is a central obstacle to storing useful work in open QB, especially when the charger itself provides an unavoidable loss channel. Here we show that such charger-induced loss can be converted into a protection mechanism by combining Purcell effect with quantum Zeno effect. We reveal that the virtual photon process and the Purcell effect can induce the strong coupling regime to the quantum Zeno regime, in which the stronger the dissipation of the charger, the weaker the self-discharging effect of the QB. As a result, the dissipation caused by the charger to the QB can be suppressed four orders of magnitude in our scheme. Meanwhile, the quantum Zeno effect induced by the Purcell effect can also avoid the energy backflow between the QB and the charger. Owing to the significantly suppressed dissipation, the stored energy of QB can be charged to a nearly full state and the stored energy is almost converted into extractable work, which greatly improves the energy conversion efficiency.

quant-ph↗

arXiv2026

Black Hole Interior and Time-like Entanglement Entropy

We establish time-like entanglement entropy (TEE) as a novel tool to characterize the black hole interior from a single-boundary perspective. In the Schwarzschild-AdS black hole, we show that TEE of time-like boundary strips exhibits linear growth as a function of temporal width in the limit of large temporal width, and that its imaginary part carries physical significance rather than being a constant. By analyzing charged, scalar-hairy black holes, we present evidence that TEE detects a hidden "causal phase transition" separating Type-I and Type-II interiors -- distinguished by singularity structure. We identify a critical temporal width $τ_c$ that acts as the order parameter for this transition: for strips narrower than $τ_c$, the system enters a distinct "time-like entanglement phase" dominated purely by time-like contributions, up to a regulator effect; conversely, for strips wider than $τ_c$, space-like entanglement re-emerges. Notably, the existence of a Cauchy horizon drives the $τ_c$ to infinity, leading to pure time-like entanglement. These results suggest that the TEE may supply a novel boundary quantum-information measure to detect structure hidden inside the black hole and suggests a deep connection between TEE and cosmic censorship.

hep-th↗

arXiv2023

Nonreciprocal Generation of Schrödinger Cat State Induced by Topology

The Schrödinger cat state produced differently in two directions is anticipated to be a critical quantum resource in quantum information technologies. By exploring the interplay between quantum nonreciprocity and topology in a one-dimensional microcavity array, we obtain the Schrödinger cat state ({\it a pure quantum state}) in a chosen direction at the edge cavity, whereas a {\it classical state} in the other direction. This {\it nonreciprocal generation of the cat state} originates from the {\it topologically protected chirality-mode excitation} in the nontrivial phase, but in the trivial phase the {\it nonreciprocal generation of cat state} vanishes. Thus, our proposal is switchable by tuning the parameters so that a topological phase transition occurs. Moreover, the obtained cat state has nonreciprocal high fidelity, nonclassicality, and quantum coherence, which are sufficient to be used in various one-way quantum technologies, e.g., invisible quantum sensing, noise-tolerant quantum computing, and chiral quantum networks. Our work provides a general approach to control quantum nonreciprocities with the topological effect, which substantially broadens the fields of nonreciprocal photonics and topological physics.

quant-ph↗