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Shi-Jie Ma

Publications and source records attributed to Shi-Jie Ma.

12 recordsLinked to original sources

Stability of a black hole under the deformation of an extended periodic potential

It has been shown that the spectrum of black hole quasi-normal modes is extremely sensitive to localized deformations of the geometry away from the potential peak. The deformation caused by a real astronomical environment will extend throughout the whole space rather than be localized in a finite region. Whether spatially extended fluctuations distributed throughout spacetime can produce similar effects remains unclear. In this work, we construct a toy model to investigate the case that the deformation of the metric is not localized but extends throughout the whole space. We study how it changes the ringdown stage of the black hole in the time domain. Using both the Pöschl-Teller and Regge-Wheeler potentials as representative backgrounds, we show that sufficiently wide spatially periodic perturbations of zero mean can trigger not only the ``spectral instability'' in the frequency domain but also black hole instabilities in the time domain. Through numerical analysis, we uncover a universal scaling relation for the instability threshold and further provide an analytical interpretation of its physical origin.

gr-qc

Near-Horizon Deformation of Metric and the Black Hole Instability

Recent time-domain analyses suggest that black hole stability may be sensitive to localized near-horizon geometric deformations, while the underlying spectral mechanism remains unclear. In this work, we systematically investigate quasi-normal mode spectra under static localized non-positive perturbations within a frequency-domain framework. We find that such deformations generically induce a new purely imaginary mode. As the deformation approaches the horizon, the imaginary part of this mode increases and eventually enters the upper half complex-frequency plane, signaling the onset of black hole instability. Numerical results reveal clear scaling relations between the critical distance for instability and the deformation strength. We further derive rigorous proofs for our discoveries in frequency domain. These results demonstrate that black hole stability under long scale is conditionally sensitive to localized deformation of metric near the horizon and establish a unified spectral framework for understanding their induced instabilities.

gr-qc

Quasinormal modes and greybody factor of charged black hole in non-commutative geometry

In this article, the quasinormal modes and greybody factor of charged black hole in non-commutative geometry are studied. Under the assumption of a uniformly distributed charge within the matter, we obtain the metric for a charged black hole in non-commutative geometry. We calculated the wave function and obtained the effective potential of three different perturbed fields with spin. Then we applied $6^{\rm{th}}$ order WKB method to analyze the quasinormal modes of the black hole and derived quasinormal frequencies. Futhermore, we discussed the greybody factor in different perturbed fields under this spacetime.

gr-qc

Thermodynamic phase transition and Joule-Thomson expansion of a quantum corrected black hole in AdS spacetime

The thermodynamics in the extended phase space of a quantum corrected black hole (BH) proposed recently is presented in this work. Our study shows that the phase transition behavior of the BH is analogous to that of conventional Schwarzschild BH in anti-de Sitter (AdS) space; however, a critical temperature exists such that when the BH temperature exceeds this critical value, the small BH phase and the large BH phase become separated, and no phase transition occurs. Due to the introduction of the quantum parameter $ξ$, the BH equation of state splits into two branches. One branch reduces to the Schwarzschild-AdS case as $ξ\to0$, with its phase transition pressure lower than the critical pressure; another branch's phase transition pressure is greater than the critical pressure. The study shows that the $T-r_{+}$ phase transition and heat capacity are similar to those of the Schwarzschild-AdS BH. The Joule-Thomson expansion is divided into two stages: in the earlier stage, the BH pressure increases until it reaches a maximum; in the later stage, the pressure gradually decreases. In each stage, the BH may undergo an inversion point, resulting in the inversion curve with two branches. In addition, each stage has a minimum inversion mass, below which any BH (in each respective stage) has no inversion point.

gr-qc

Estimating the strength of Lorentzian distribution in non-commutative geometry by solar system tests

In this paper, we study four classical tests of Schwarzschild space-time with Lorentzian distribution in non-commutative geometry. We performed detailed calculations of the first-order corrections induced by the non-commutative parameter on planetary orbital precession, light deflection, radar wave delay, and gravitational redshift. The study showed that the impact of the non-commutative parameter on the time-like geodesics is significantly greater than its effect on the null geodesics. By using a series of precise experimental observations, the allowable range for the non-commutative parameter is ultimately constrained within $Θ\leq0.067579~\mathrm{m}^{2}$, which is given by Mercury's orbital precession. This result aligns with the view that $\sqrtΘ$ is of the order of the Planck length. Moreover, this constrained parameter range exceeds the Planck scale by a significant margin.

gr-qc

Thermodynamic properties and Joule-Thomson expansion of AdS black hole with Gaussian distribution in non-commutative geometry

The thermodynamics and Joule-Thomson expansion of anti-de Sitter black hole (AdS BH) with Gaussian distribution in non-commutative geometry is systematically studied. The metric of Gaussian-distributed BH is obtained, showing a dS geometry at the core of BH. The research indicates that the BH characterized by a Gaussian distribution exhibit thermodynamic properties that are remarkably similar to those of BH with a Lorentzian distribution in non-commutative geometry. This similarity is specifically manifested in the small BH-large BH phase transition, the corrected first law of thermodynamics, the criticality, the heat capacity, the zeroth-order phase transition and the Joule-Thomson process. Notably, the critical ratio of Gaussian-distributed BH (0.46531) is significantly larger than those observed in Van der Waals fluids (0.375), and indeed, it is also substantially exceed those of Lorentzian-distributed BH (0.36671). Moreover, compared to the case of Lorentzian source, the zeroth-order phase transition effect in Gaussian-distributed BH is exceedingly subtle (accompanied by a relative increase in the Gibbs free energy on the order of $10^{-3}\!\sim\!\!10^{-2}$) and is difficult to detect distinctly.

gr-qc

Thermodynamics of Schwarzschild-AdS black hole in non-commutative geometry

In this paper, we study the thermodynamics of Schwarzschild-anti-de Sitter black holes within the framework of non-commutative geometry. By solving the Einstein's equations, we derive the corrected Schwarzschild-AdS black hole with Lorentzian distribution and analyze the thermodynamics. Our results confirm that if the energy-momentum tensor outside the event horizon is related to the mass of the black hole, the conventional first law of thermodynamics will be violated. The study of criticality reveals that the black hole undergoes a small black hole-large black hole phase transition similar to that of the Van der Waals system, with a critical point and a critical ratio slightly smaller than that of the Van der Waals fluid. As the non-commutative parameter increases, the phase transition process shortens, leading to a critical point, and ultimately to the disappearance of the phase transition. The violation of the conventional first law results in a discontinuity of the Gibbs free energy during the phase transition, indicating the occurrence of zeroth-order phase transition. Moreover, we investigate the Joule-Thomson expansion, obtaining the minimum inversion temperature and the minimum inversion mass.

gr-qc

Thermodynamics of AdS-Schwarzschild-like black hole in loop quantum gravity

We obtained the metric of the Schwarzschild-like black hole with loop quantum gravity (LQG) corrections in anti-de Sitter (AdS) space-time, under the assumption that the cosmological constant is decoupled in LQG. We investigated its thermodynamics, including the equation of state, criticality, heat capacity, and Gibbs free energy. The $P-v$ graph was plotted, and the critical behavior was calculated. It was found that, due to the LQG effect, the quantum-corrected Schwarzschild-AdS black hole exhibits a critical point and a critical ratio of $7/18$, which differs from the Reissner-Nordstr$\ddot{\mathrm{o}}$m-AdS black hole's ratio of $3/8$ (the same as that of the Van der Waals system) slightly. However, there are still some similarities compared to the Van der Waals system, such as the same critical exponents and a similar $P-v$ graph. Moreover, it is concluded that the energy-momentum tensor related to the black hole's mass could violate the conventional first law of thermodynamics. This modified first law may violate the conservation of Gibbs free energy during the small black hole-large black hole phase transitions, potentially indicating the occurrence of the zeroth-order phase transition. The Joule-Thomson expansion was also studied. Interestingly, compared to the Schwarzschild-AdS black hole, the LQG effect leads to inversion points. The inversion curve divides the $\left(P,T\right)$ coordinate system into two regions: a heating region and a cooling region, as shown in detail by the inversion curves and isenthalpic curves. The results indicated that there is a minimum inversion mass, below which any black hole will not possess an inversion point.

gr-qc

A Study of Decay Rate of Bound Negative Muons

A number of experiments show that the decay lifetimes of muons bound to atomic nuclei are longer than the decay lifetimes of free muons. In this paper, a scheme of extending quantum mechanics (EQM) is proposed to resolve this problem. The Schr$\ddot{\text{o}}$dinger's equation is obtained to prove the validation of this attempt. The decay ratio of bound muons is also calculated in EQM, and the result is in good agreement with the experimental data.

hep-ph

Euler-Heisenberg black hole surrounded by perfect fluid dark matter

A generation method of new metric in the case of static spherically symmetric space-time is derived. Using this approach, we construct a metric which describes Euler-Heisenberg black hole surrounded by perfect fluid dark matter and investigate its optical and thermodynamic properties. We found that radius of shadow will increase with the increase of dark matter effect, and more strong dark matter will diminish the light intensity of accretion disk generally. Moreover, in thermodynamics, when quantum electrodynamic parameter is positive, there will be a critical value of dark matter parameter, which determine the number of black hole's critical points.

gr-qc

Optical properties of Euler-Heisenberg black hole in the Cold Dark Matter Halo

The optical properties of Euler-Heisenberg (EH) black hole (BH) surrounded by Cold Dark Matter (CDM) halo are investigated. By changing BH's parameters, we found that the radius of horizon r_{h} and radius of photon sphere r_{ph} will transparently increase as CDM halo parameters R and ρincrease. To show the influence of CDM halo on the BH's optical characteristics, we took two sets of R and ρwith prominent differences and plot the first four orders of images for thin accretion disk with different angle of inclination θof observer. The images with light intensity distributions using Novikov-Thorne (N-T) model are also derived, as well as the effective potential, photon orbits. Especially, analysis of intersection behaviors between photon trajectories with different impact parameters and circular time-like orbits in accretion disk will help better understand the image of thin accretion disk. Our results showed that CDM halo will make BH become more larger and dimmer distinctly.

gr-qc

Shadow of Schwarzschild Black Hole in the Cold Dark Matter Halo

The Schwarzschild black hole in the Cold Dark Matter (CDM) halo is studied, and the radiation laws of the thin accretion disk near the black hole are discussed and summarized. The orbits of light around the black hole are also calculated. Additionally, using the Novikov-Thorne model's light intensity function of the thin accretion disk, it is possible to solve for the shadow created by the thin accretion disk near the Schwarzschild black hole as well as the observed luminosity of the disk.

gr-qc