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A point source at the photon sphere of a black-hole lens: (a) the ray trajectories; (b) the field pattern. (c) Parallel light rays incident to the black-hole lens. (d) Gaussian beam incident to the black-hole lens.
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![FIG. 1. A point source inside the de Sitter profile [Eq. (5)]: (a) the...](profile/Sicen-Tao/publication/343872670/figure/fig1/AS:934697710411776@1599860708202/A-point-source-inside-the-de-Sitter-profile-Eq-5-a-the-ray-trajectories-b-the_Q320.jpg)
Recent observation of black hole and gravitational wave has stirred up great interest in Einstein's general relativity. In an optical system, the “optical black hole” has also been a key topic in mimicking black holes. Another good way to study or mimic general relativity effects is based on transformation optics. In this paper, we propose a way by...
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... which is mapped from r = 3L 2 (see Appendix A). In Fig. 2(a), we put a point source at the photon sphere. We find that part of the rays will escape from the black hole, and part will be trapped by the photon sphere and approach the horizon perpendicularly. In fact, for the rays that emit to the left direction, which is under the photon sphere, they will all be trapped and incident on the event ...
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... emit to the left direction, which is under the photon sphere, they will all be trapped and incident on the event horizon perpendicularly, while for the rays that emit to the right direction, which is outside the photon sphere, they will all be bent and escape the event horizon. We also plot the field pattern in wave optics for a point source in Fig. 2(b). The waves will interfere with each other at the opposite site of the source. The same trick was used here that we make the radius of horizon slightly larger in wave simulations ...
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... L is 1) to better present the field pattern and prevent wave approaching the singularity of the event horizon. The same way is applied to Fig. ...
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... is because of the photon sphere that we could see the donutlike halo from the earth [3]. We therefore study the case of parallel light rays incident to the black hole in Fig. 2(c). For rays outside the photon sphere, they will be bent due to the gravitational lens effect of the black hole. For the rays incident almost tangential to the photon sphere, they will propagate in a U-turn trajectory, just like the Eaton lens [43,44]. For the rays impinging at the photon sphere, they will all be trapped and approach the ...
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... to the photon sphere, they will propagate in a U-turn trajectory, just like the Eaton lens [43,44]. For the rays impinging at the photon sphere, they will all be trapped and approach the horizon perpendicularly. We also study the case for wave optics, i.e., an incident Gaussian beam interacts with the black hole. The field pattern is plotted in Fig. 2(d), where we can see that the wave will be absorbed in the middle part, while those outside the photon sphere could escape and will interfere with each other at the opposite site. For simplicity, the above simulations are performed in two dimensions. Obviously, our model could, at least in the optical system, commendably mimic the real ...
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... which is mapped from r = 3L 2 (see Appendix A). In Fig. 2(a), we put a point source at the photon sphere. We find that part of the rays will escape from the black hole, and part will be trapped by the photon sphere and approach the horizon perpendicularly. In fact, for the rays that emit to the left direction, which is under the photon sphere, they will all be trapped and incident on the event ...
Context 7
... emit to the left direction, which is under the photon sphere, they will all be trapped and incident on the event horizon perpendicularly, while for the rays that emit to the right direction, which is outside the photon sphere, they will all be bent and escape the event horizon. We also plot the field pattern in wave optics for a point source in Fig. 2(b). The waves will interfere with each other at the opposite site of the source. The same trick was used here that we make the radius of horizon slightly larger in wave simulations ...
Context 8
... L is 1) to better present the field pattern and prevent wave approaching the singularity of the event horizon. The same way is applied to Fig. ...
Context 9
... is because of the photon sphere that we could see the donutlike halo from the earth [3]. We therefore study the case of parallel light rays incident to the black hole in Fig. 2(c). For rays outside the photon sphere, they will be bent due to the gravitational lens effect of the black hole. For the rays incident almost tangential to the photon sphere, they will propagate in a U-turn trajectory, just like the Eaton lens [43,44]. For the rays impinging at the photon sphere, they will all be trapped and approach the ...
Context 10
... to the photon sphere, they will propagate in a U-turn trajectory, just like the Eaton lens [43,44]. For the rays impinging at the photon sphere, they will all be trapped and approach the horizon perpendicularly. We also study the case for wave optics, i.e., an incident Gaussian beam interacts with the black hole. The field pattern is plotted in Fig. 2(d), where we can see that the wave will be absorbed in the middle part, while those outside the photon sphere could escape and will interfere with each other at the opposite site. For simplicity, the above simulations are performed in two dimensions. Obviously, our model could, at least in the optical system, commendably mimic the real ...
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Citations
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