圈量子引力中带电黑洞的吸收谱与灰体因子
Absorption spectrum and greybody factors of charged black holes in loop quantum gravity
AI总结：
该研究计算了带电圈量子引力黑洞的无质量标量波吸收截面与灰体因子，分析了量子参数、电荷质量比对吸收谱的影响，并与雷斯纳-诺德斯特龙黑洞及经典近似结果对比，为理解这类黑洞的吸收性质奠定了基础。
AI中文摘要：
在过去几十年里，在圈量子引力（Loop Quantum Gravity，LQG）框架下得到的无奇点黑洞（black holes，BHs）已在文献中受到关注。这些致密天体用一个名为反弹半径的过渡超曲面取代了经典奇点，是探索LQG在黑洞物理学中印记的潜在场景。尽管目前正在研究基于LQG的黑洞附近的标量扰动，但吸收谱尚未被详细分析。在这项工作中，我们深入研究了无质量试验标量场被带电LQG黑洞吸收的性质，旨在更好地理解黑洞时空的量子参数与电荷参数所起的作用。我们采用数值方法，针对入射波频率的任意值计算了无质量标量波的吸收截面（absorption cross section，ACS）。我们发现，随着量子参数的增大，吸收截面的峰和谷呈现相反的行为，即对应最高峰值的曲线会出现最深的谷。此外，我们表明，随着黑洞电荷质量比的增大，吸收截面会减小，这与改变量子参数时吸收谱的行为形成鲜明对比。我们还将结果与雷斯纳-诺德斯特龙（Reissner-Nordstrom，RN）黑洞进行了比较，探讨了LQG黑洞与RN黑洞具有相同吸收性质的情形。此外，我们发现我们的数值结果与总吸收截面在相应极限下的经典和半经典近似吻合良好。为了完整起见，我们还研究了灰体因子。我们的结果可被视为进一步理解受LQG启发的黑洞吸收性质的第一步。
英文摘要：
In the last few decades, singularity-free black holes (BHs) obtained in the framework of Loop Quantum Gravity (LQG) have gained attention in the literature. These compact objects replace the classical singularity with a transition hypersurface called the bounce radius and stand out as potential scenarios for exploring the imprints of LQG in BH physics. Although scalar perturbations in the vicinity of LQG-based BHs are currently being studied, the absorption spectrum has not yet been analyzed in detail. In this work, we present an in-depth investigation of the absorption properties of massless test scalar fields by a charged LQG BH, aiming to better understand the role played by the quantum and charge parameters of the BH spacetime. Using a numerical approach, we compute the absorption cross section (ACS) of the massless scalar wave for arbitrary values of the frequency of the incident wave. We find that the behavior of the ACS as we increase the quantum parameter indicates that the peaks and troughs of the total ACS exhibit opposite behaviors, i.e., the curve related to the highest peak corresponds to the deepest troughs. Moreover, we show that the ACS decreases as we consider higher values of the BH charge-to-mass ratio. This is in stark contrast to the behavior of the absorption spectrum as we vary the quantum parameter. We also draw comparisons with the Reissner-Nordstrom (RN) BH, exploring the situations where LQG and RN BHs can have the same absorption properties. Furthermore, we find excellent agreement between our numerical results and the well-known classical and semiclassical approximations for the total ACS in their corresponding limits. For completeness, we also investigate the greybody factors. Our results can be viewed as a first step toward a better understanding of the absorption properties of LQG-inspired BHs.
