Recent progress on the black hole information paradox has succeeded in reconstructing Page curves... more Recent progress on the black hole information paradox has succeeded in reconstructing Page curves compatible with unitary evolution. The formula of generalized entropy derived from the gravitational path integration, nevertheless, does not provide concrete insight on how the information comes out from the black hole given that the state of the radiation seems to follow what was given by Hawking. In this paper, we provide a quantum informational interpretation of entanglement islands and draw the parallel between the black hole information paradox and the problems of measurements in quantum mechanics. We show that the Page curve can be realized by effective Bell-basis measurements on the entanglement island. We argue that such interpretation is necessary for a quantum informational model if smooth horizons and bulk reconstruction are assumed, and show how it explains the Page curves of solvable models of 2D gravity. The correspondences between concepts in black hole studies and that ...
In this study, we apply quantum master equations beyond secular approximation, and investigate th... more In this study, we apply quantum master equations beyond secular approximation, and investigate the nonequilibrium thermodynamic cost of enhanced quantum metrology and quantum correlations. We find that the nonequilibrium conditions enhance quantum Fisher information (QFI) and quantum correlations predominantly for weak tunneling scenarios. The enhancement is assisted by a corresponding increase of the thermodynamic cost characterized by the entropy production rate (EPR). For the strong tunneling regimes, the QFI and quantum correlations can not be unceasingly boosted by higher thermodynamic costs and decay once the system is overburdened with extremely large energy currents. The result indicates that for open systems with weak tunneling rates, thermodynamic cost can be potentially exploited to improve the quantum metrology and quantum correlations.
Fluctuations associated with relaxations in far-from-equilibrium regime is of fundamental interes... more Fluctuations associated with relaxations in far-from-equilibrium regime is of fundamental interest for a large variety of systems within broad scales. Recent advances in techniques such as spectroscopy have generated the possibility for measuring the fluctuations of the mesoscopic systems in connection to the relaxation processes when driving the underlying quantum systems far from equilibrium. We present a general nonequilibrium Fluctuation-Dissipation Theorem (FDT) for quantum Markovian processes where the detailed-balance condition is violated. Apart from the fluctuations, the relaxation involves extra correlation that is governed by the quantum curl flux emerged in the far-from-equilibrium regime. Such a contribution vanishes for the thermal equilibrium, so that the conventional FDT is recovered. We finally apply the nonequilibrium FDT to the molecular junctions, elaborating the detailed-balance-breaking effects on the optical transmission spectrum. Our results have the advantag...
We study the quantum conditional entropy production, which quantifies the irreversibly conditione... more We study the quantum conditional entropy production, which quantifies the irreversibly conditioned on the coupling memory of the system. We prove that the quantum unconditional entropy production is less than the conditional one, where the latter has contribution from the informational nonequilibriumness. The mismatch, defined as the quantum dissipative information, pinpoints the distributive correlation established between the environment and the memory. Although the quantum unconditional entropy production can be zero, the conditional one is in general not, which is beyond the thermal equilibrium. Positive quantum dissipative information characterizes a potential work waste. We also prove the quantum fluctuation theorems related to the conditional entropy production, based on different two-point measurement schemes. The dissipative information itself also follows the quantum fluctuation theorem. We present examples based on the qubit collisional model and the qubit Maxwell’s demon.
We apply the recently proposed quantum extremal surface construction to calculate the Page curve ... more We apply the recently proposed quantum extremal surface construction to calculate the Page curve of the eternal Reissner-Nordström black holes in four dimensions. Without the island, the entropy of Hawking radiation grows linearly with time, which results in the information paradox for the eternal black holes. By extremizing the generalized entropy that allows the contributions from the island, we find that the island extends outside the horizon of the Reissner-Nordström black hole. When taking into the effect of the islands, it is shown that the entanglement entropy of Hawking radiation at late times for a given region far from the black hole horizon reproduces the Bekenstein-Hawking entropy of Reissner-Nordström black hole with an additional term representing the effect of the matter fields. The result is consistent with the finiteness of the entanglement entropy for the radiation from an eternal black hole and resolves the information paradox for this case. Equal contributions Co...
By using the quantum extremal island formula, we perform a simple calculation of the generalized ... more By using the quantum extremal island formula, we perform a simple calculation of the generalized entanglement entropy of Hawking radiation from the two dimensional Liouville black hole. No reasonable island was found when extremizing the generalized entropy. This suggests that the islands may not necessarily save the information paradox for the Liouville black holes. ∗liran@htu.edu.cn †xuanhua.wang@stonybrook.edu ‡Corresponding author: jin.wang.1@stonybrook.edu 1 ar X iv :2 10 5. 03 27 1v 1 [ he pth ] 7 M ay 2 02 1
Strong molecule-light interaction enables the control of molecular structures and dynamical proce... more Strong molecule-light interaction enables the control of molecular structures and dynamical processes. A molecular model is proposed to greatly enhance the intermolecular distance of resonant energy transfer, where the molecules are strongly driven by an optical cavity. The optimal intermolecular distance and quantum yield of energy transfer are observed, resulting from the balance between dipole-dipole interaction and molecule-cavity coupling. Our approach is {\textit{non-perturbative}}, going much beyond the Forster mechanism of resonant energy transfer. Our work sheds the light on the spectroscopic study of the cooperative energy transfer in molecular polaritons.
Strong molecule-light interaction enables the control of molecular structures and dynamical proce... more Strong molecule-light interaction enables the control of molecular structures and dynamical processes. A model with a strong laser drive is proposed to greatly enhance the intermolecular distance of resonant energy transfer, where the molecules are strongly driven by an optical cavity. The optimal Rabi frequency and quantum yield of energy transfer are observed, resulting from the trade-off between dipole-dipole interaction and molecule-cavity coupling. When the strong drive at a certain Rabi frequency is applied, a larger spatial range of effective energy transfer and a slower decay rate with the distance compared to the Förster mechanism of resonant energy transfer are observed in our model. Our work sheds light on the spectroscopic study of cooperative energy transfer in molecular polaritons.
We study the entanglement entropy of a one-parameter family of exactly solvable gravities in the ... more We study the entanglement entropy of a one-parameter family of exactly solvable gravities in the 2-dimensional asymptotically-flat space. The islands and Page curves of eternal, evaporating and bath-removed black holes are investigated. The different theories in this parameter class are identified through field redefinitions which leave the island invariant. The Page transition is found to occur at the first a third of the black hole life time in the evaporating case for this family of solutions. In addition, we consider gluing the equilibrium black hole and the evaporating one along a null trajectory and study the effect of gluing on the islands and Page curves. In the glued space, the island jumps across two different geometries at a certain retarded time. As a result, the Page transition is stretched and split into two separate ones-the first transition happens when the net entropy generation stops and the second one occurs as the early radiation effectively starts to become purified. Finally, we discuss the issues concerning the inconsistent rates of purification and the paradox related to the state of the radiation.
Recent progress on the black hole information paradox has succeeded in reconstructing Page curves... more Recent progress on the black hole information paradox has succeeded in reconstructing Page curves compatible with unitary evolution. The formula of generalized entropy derived from the gravitational path integration, nevertheless, does not provide concrete insight on how the information comes out from the black hole given that the state of the radiation seems to follow what was given by Hawking. In this paper, we provide a quantum informational interpretation of entanglement islands and draw the parallel between the black hole information paradox and the problems of measurements in quantum mechanics. We show that the Page curve can be realized by effective Bell-basis measurements on the entanglement island. We argue that such interpretation is necessary for a quantum informational model if smooth horizons and bulk reconstruction are assumed, and show how it explains the Page curves of solvable models of 2D gravity. The correspondences between concepts in black hole studies and that ...
In this study, we apply quantum master equations beyond secular approximation, and investigate th... more In this study, we apply quantum master equations beyond secular approximation, and investigate the nonequilibrium thermodynamic cost of enhanced quantum metrology and quantum correlations. We find that the nonequilibrium conditions enhance quantum Fisher information (QFI) and quantum correlations predominantly for weak tunneling scenarios. The enhancement is assisted by a corresponding increase of the thermodynamic cost characterized by the entropy production rate (EPR). For the strong tunneling regimes, the QFI and quantum correlations can not be unceasingly boosted by higher thermodynamic costs and decay once the system is overburdened with extremely large energy currents. The result indicates that for open systems with weak tunneling rates, thermodynamic cost can be potentially exploited to improve the quantum metrology and quantum correlations.
Fluctuations associated with relaxations in far-from-equilibrium regime is of fundamental interes... more Fluctuations associated with relaxations in far-from-equilibrium regime is of fundamental interest for a large variety of systems within broad scales. Recent advances in techniques such as spectroscopy have generated the possibility for measuring the fluctuations of the mesoscopic systems in connection to the relaxation processes when driving the underlying quantum systems far from equilibrium. We present a general nonequilibrium Fluctuation-Dissipation Theorem (FDT) for quantum Markovian processes where the detailed-balance condition is violated. Apart from the fluctuations, the relaxation involves extra correlation that is governed by the quantum curl flux emerged in the far-from-equilibrium regime. Such a contribution vanishes for the thermal equilibrium, so that the conventional FDT is recovered. We finally apply the nonequilibrium FDT to the molecular junctions, elaborating the detailed-balance-breaking effects on the optical transmission spectrum. Our results have the advantag...
We study the quantum conditional entropy production, which quantifies the irreversibly conditione... more We study the quantum conditional entropy production, which quantifies the irreversibly conditioned on the coupling memory of the system. We prove that the quantum unconditional entropy production is less than the conditional one, where the latter has contribution from the informational nonequilibriumness. The mismatch, defined as the quantum dissipative information, pinpoints the distributive correlation established between the environment and the memory. Although the quantum unconditional entropy production can be zero, the conditional one is in general not, which is beyond the thermal equilibrium. Positive quantum dissipative information characterizes a potential work waste. We also prove the quantum fluctuation theorems related to the conditional entropy production, based on different two-point measurement schemes. The dissipative information itself also follows the quantum fluctuation theorem. We present examples based on the qubit collisional model and the qubit Maxwell’s demon.
We apply the recently proposed quantum extremal surface construction to calculate the Page curve ... more We apply the recently proposed quantum extremal surface construction to calculate the Page curve of the eternal Reissner-Nordström black holes in four dimensions. Without the island, the entropy of Hawking radiation grows linearly with time, which results in the information paradox for the eternal black holes. By extremizing the generalized entropy that allows the contributions from the island, we find that the island extends outside the horizon of the Reissner-Nordström black hole. When taking into the effect of the islands, it is shown that the entanglement entropy of Hawking radiation at late times for a given region far from the black hole horizon reproduces the Bekenstein-Hawking entropy of Reissner-Nordström black hole with an additional term representing the effect of the matter fields. The result is consistent with the finiteness of the entanglement entropy for the radiation from an eternal black hole and resolves the information paradox for this case. Equal contributions Co...
By using the quantum extremal island formula, we perform a simple calculation of the generalized ... more By using the quantum extremal island formula, we perform a simple calculation of the generalized entanglement entropy of Hawking radiation from the two dimensional Liouville black hole. No reasonable island was found when extremizing the generalized entropy. This suggests that the islands may not necessarily save the information paradox for the Liouville black holes. ∗liran@htu.edu.cn †xuanhua.wang@stonybrook.edu ‡Corresponding author: jin.wang.1@stonybrook.edu 1 ar X iv :2 10 5. 03 27 1v 1 [ he pth ] 7 M ay 2 02 1
Strong molecule-light interaction enables the control of molecular structures and dynamical proce... more Strong molecule-light interaction enables the control of molecular structures and dynamical processes. A molecular model is proposed to greatly enhance the intermolecular distance of resonant energy transfer, where the molecules are strongly driven by an optical cavity. The optimal intermolecular distance and quantum yield of energy transfer are observed, resulting from the balance between dipole-dipole interaction and molecule-cavity coupling. Our approach is {\textit{non-perturbative}}, going much beyond the Forster mechanism of resonant energy transfer. Our work sheds the light on the spectroscopic study of the cooperative energy transfer in molecular polaritons.
Strong molecule-light interaction enables the control of molecular structures and dynamical proce... more Strong molecule-light interaction enables the control of molecular structures and dynamical processes. A model with a strong laser drive is proposed to greatly enhance the intermolecular distance of resonant energy transfer, where the molecules are strongly driven by an optical cavity. The optimal Rabi frequency and quantum yield of energy transfer are observed, resulting from the trade-off between dipole-dipole interaction and molecule-cavity coupling. When the strong drive at a certain Rabi frequency is applied, a larger spatial range of effective energy transfer and a slower decay rate with the distance compared to the Förster mechanism of resonant energy transfer are observed in our model. Our work sheds light on the spectroscopic study of cooperative energy transfer in molecular polaritons.
We study the entanglement entropy of a one-parameter family of exactly solvable gravities in the ... more We study the entanglement entropy of a one-parameter family of exactly solvable gravities in the 2-dimensional asymptotically-flat space. The islands and Page curves of eternal, evaporating and bath-removed black holes are investigated. The different theories in this parameter class are identified through field redefinitions which leave the island invariant. The Page transition is found to occur at the first a third of the black hole life time in the evaporating case for this family of solutions. In addition, we consider gluing the equilibrium black hole and the evaporating one along a null trajectory and study the effect of gluing on the islands and Page curves. In the glued space, the island jumps across two different geometries at a certain retarded time. As a result, the Page transition is stretched and split into two separate ones-the first transition happens when the net entropy generation stops and the second one occurs as the early radiation effectively starts to become purified. Finally, we discuss the issues concerning the inconsistent rates of purification and the paradox related to the state of the radiation.
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