Archived weekly pre-prints 24-01-08
Fri - 01/05/24
Loop quantum gravity related papers
There is no new related paper today
Spin foam related papers
There is no new related paper today
Other related papers
- [2401.01939] - The Standard Model from String Theory: What Have We Learned? - Fernando Marchesano, Gary Shiu, Timo Weigand
Thu - 01/04/24
Loop quantum gravity related papers
There is no new related paper today
Spin foam related papers
There is no new related paper today
Other related papers
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[2401.01767] - Absorption and (unbounded) superradiance in a static regular black hole spacetime - Marco A. A. de Paula, Luiz C. S. Leite, Sam R. Dolan, Luís C. B. Crispino
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[2401.01617] - Holographic Approach to Neutron Stars - Tinglong Feng
Wed - 01/03/24
Loop quantum gravity related papers
There is no new related paper today
Spin foam related papers
There is no new related paper today
Other related papers
- [2401.01287] - To Wedge Or Not To Wedge, Wedges and operator reconstructability in toy models of AdS/CFT - Vic Vander Linden
Tue - 01/02/24
Loop quantum gravity related papers
Quantum measure as a necessary ingredient in quantum gravity and modified gravities
- Authors: Vladimir Dzhunushaliev, Vladimir Folomeev
- Subjects: General Relativity and Quantum Cosmology (gr-qc)
- Arxiv link: https://arxiv.org/abs/2312.17546
- Abstract We suggest commutation relations for a quantum measure. In one version of these relations, the right-hand side takes account of the presence of curvature of space; in the simplest case, this yields the action of general relativity. We consider the cases of the quantization of the measure on spaces of constant curvature and show that in this case the commutation relations for the quantum measure are analogues of commutation relations in loop quantum gravity. It is assumed that, in contrast to loop quantum gravity, a triangulation of space is a necessary trick for quantizing such a nonlocal quantity like a measure; in doing so, the space remains a smooth manifold. We consider the self-consistent problem of the interaction of the quantum measure and classical gravitation. It is shown that this inevitably leads to the appearance of modified gravities. Also, we consider the problem of defining the Euler-Lagrange equations for a matter field in the background of a space endowed with quantum measure.
Shadows and photon rings of a quantum black hole
- Authors: Jing-Peng Ye, Zhi-Qing He, Ai-Xu Zhou, Zi-Yang Huang, Jia-Hui Huang
- Subjects: General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Theory (hep-th)
- Arxiv link: https://arxiv.org/abs/2312.17724
- Abstract Recently, a black hole model in loop quantum gravity has been proposed by Lewandowski, Ma, Yang and Zhang (Phys. Rev. Lett. \textbf{130}, 101501 (2023)). The metric tensor of the quantum black hole (QBH) is a suitably modified Schwarzschild one. In this paper, we calculate the radius of light ring and obtain the linear approximation of it with respect to the quantum correction parameter $\alpha$: $r_{l} \simeq 3 M - \frac{\alpha}{9 M}$. We then assume the QBH is backlit by a large, distant plane of uniform, isotropic emission and calculate the radius of the black hole shadow and its linear approximation: $r_{s} = 3 \sqrt{3} M - \frac{\alpha}{6 \left(\sqrt{3} M\right)}$. We also consider the photon ring structures in the shadow when the impact parameter $b$ of the photon approaches to a critical impact parameter $b_{\textrm{c}}$, and obtain a formula for estimating the deflection angle, which is $\varphi_{\textrm{def}} = - \frac{\sqrt{2}}{\omega r_{l}^2}\log{\left(b - b_c\right) + \widetilde{C}(b)}$. We also numerically plot the images of shadows and photon rings of the QBH in three different illumination models and compare them with that of a Schwarzschild in each model. It is found that we could distinguish the quantum black hole with a Schwarzschild black hole by the shadow images in certain specific illumination model.
Spin foam related papers
There is no new related paper today
Other related papers
-
[2312.17335] - Graviton Noise Correlation in Nearby Detectors - Maulik Parikh, Francesco Setti
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[2312.17639] - Quasinormal modes of quantum-corrected black holes - Huajie Gong, Shulan Li, Dan Zhang, Guoyang Fu, Jian-Pin Wu
Mon - 01/01/24
Loop quantum gravity related papers
Quantum measure as a necessary ingredient in quantum gravity and modified gravities
- Authors: Vladimir Dzhunushaliev, Vladimir Folomeev
- Subjects: General Relativity and Quantum Cosmology (gr-qc)
- Arxiv link: https://arxiv.org/abs/2312.17546
- Abstract We suggest commutation relations for a quantum measure. In one version of these relations, the right-hand side takes account of the presence of curvature of space; in the simplest case, this yields the action of general relativity. We consider the cases of the quantization of the measure on spaces of constant curvature and show that in this case the commutation relations for the quantum measure are analogues of commutation relations in loop quantum gravity. It is assumed that, in contrast to loop quantum gravity, a triangulation of space is a necessary trick for quantizing such a nonlocal quantity like a measure; in doing so, the space remains a smooth manifold. We consider the self-consistent problem of the interaction of the quantum measure and classical gravitation. It is shown that this inevitably leads to the appearance of modified gravities. Also, we consider the problem of defining the Euler-Lagrange equations for a matter field in the background of a space endowed with quantum measure.
Shadows and photon rings of a quantum black hole
- Authors: Jing-Peng Ye, Zhi-Qing He, Ai-Xu Zhou, Zi-Yang Huang, Jia-Hui Huang
- Subjects: General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Theory (hep-th)
- Arxiv link: https://arxiv.org/abs/2312.17724
- Abstract Recently, a black hole model in loop quantum gravity has been proposed by Lewandowski, Ma, Yang and Zhang (Phys. Rev. Lett. \textbf{130}, 101501 (2023)). The metric tensor of the quantum black hole (QBH) is a suitably modified Schwarzschild one. In this paper, we calculate the radius of light ring and obtain the linear approximation of it with respect to the quantum correction parameter $\alpha$: $r_{l} \simeq 3 M - \frac{\alpha}{9 M}$. We then assume the QBH is backlit by a large, distant plane of uniform, isotropic emission and calculate the radius of the black hole shadow and its linear approximation: $r_{s} = 3 \sqrt{3} M - \frac{\alpha}{6 \left(\sqrt{3} M\right)}$. We also consider the photon ring structures in the shadow when the impact parameter $b$ of the photon approaches to a critical impact parameter $b_{\textrm{c}}$, and obtain a formula for estimating the deflection angle, which is $\varphi_{\textrm{def}} = - \frac{\sqrt{2}}{\omega r_{l}^2}\log{\left(b - b_c\right) + \widetilde{C}(b)}$. We also numerically plot the images of shadows and photon rings of the QBH in three different illumination models and compare them with that of a Schwarzschild in each model. It is found that we could distinguish the quantum black hole with a Schwarzschild black hole by the shadow images in certain specific illumination model.
Spin foam related papers
There is no new related paper today
Other related papers
-
[2312.17335] - Graviton Noise Correlation in Nearby Detectors - Maulik Parikh, Francesco Setti
-
[2312.17639] - Quasinormal modes of quantum-corrected black holes - Huajie Gong, Shulan Li, Dan Zhang, Guoyang Fu, Jian-Pin Wu