The effect of Hawking radiation on the redistribution of the entanglement and mutual information in the Schwarzschild spacetime is investigated. Our analysis shows that the physically accessible correlations degrade while the unaccessible correlation
s increase as the Hawking temperature increases because the initial correlations described by inertial observers are redistributed between all the bipartite modes. It is interesting to note that, in the limit case that the temperature tends to infinity, the accessible mutual information equals to just half of its initial value, and the unaccessible mutual information between mode $A$ and $II$ also equals to the same value.
Quantum decoherence, which appears when a system interacts with its environment in an irreversible way, plays a fundamental role in the description of quantum-to-classical transitions and has been successfully applied in some important experiments. H
ere, we study the decoherence in noninertial frames for the first time. It is shown that the decoherence and loss of the entanglement generated by the Unruh effect will influence each other remarkably. It is interesting to note that in the case of the total system under decoherence, the sudden death of entanglement may appear for any acceleration. However, in the case of only Robs qubit underging decoherence sudden death may only occur when the acceleration parameter is greater than a critical point.
We investigate the propagation and evolution for a massless scalar field in the background of $lambda=1/2$ Hov{r}ava-Lifshitz black hole with the condition of detailed balance. We fortunately obtain an exact solution for the Klein-Gordon equation. Th
en, we find an analytical expression for the greybody factor which is valid for any frequency; and also exactly show that the perturbation decays without any oscillation. All of these can help us to understand more about the Hov{r}ava-Lifshitz gravity.
We study holographic superconductors in a Hov{r}ava-Lifshitz black hole without the condition of the detailed balance. We show that it is easier for the scalar hair to form as the parameter of the detailed balance becomes larger, but harder when the
mass of the scalar field larger. We also find that the ratio of the gap frequency in conductivity to the critical temperature, $omega_{g}/T_c$, almost linear decreases with the increase of the balance constant. For $epsilon= 0$ the ratio reduces to Cais result $omega_g/T_capprox 13$ found in the Hov{r}ava-Lifshitz black hole with the condition of the detailed balance, while as $epsilon rightarrow 1$ it tends to Horowitz-Roberts relation $omega_g/T_capprox 8$ obtained in the AdS Schwarzschild black hole. Our result provides a bridge between the results for the Hv{o}rava-Lifshitz theory with the condition of the detailed balance and Einsteins gravity.
We study the first law of thermodynamics in IR modified Hv{o}rava-Lifshitz spacetime. Based on the Bekenstein-Hawking entropy, we obtain the integral formula and the differential formula of the first law of thermodynamics for the Kehagias-Sfetsos bla
ck hole by treating $omega$ as a new state parameter and redefining a mass that is just equal to $M_{ADM}$ obtained by Myungcite{YSM2} if we take $alpha=3pi/8$.
The classical and quantum correlations sharing between modes of the Dirac fields in the noninertial frame are investigated. It is shown that: (i) The classical correlation for the Dirac fields decreases as the acceleration increases, which is differe
nt from the result of the scalar field that the classical correlation is independent of the acceleration; (ii) There is no simple dominating relation between the quantum correlation and entanglement for the Dirac fields, which is unlike the scalar case where the quantum correlation is always over and above the entanglement; (iii) As the acceleration increases, the correlations between modes $I$ and $II$ and between modes $A$ and $II$ increase, but the correlations between modes $A$ and $I$ decrease.
We study the dynamical evolution of a massless scalar perturbation in the Hov{r}ava-Lifshitz black-hole spacetimes with the coupling constants $lambda={1/3}$, $lambda={1/2}$ and $lambda=3$, respectively. Our calculation shows that, for the three case
s, the scalar perturbations decay without any oscillation in which the decay rate imprints the parameter of the Hov{r}ava-Lifshitz black hole. The results are quite different from those in the Schwarzschild AdS black hole and can help us understand more about the Hov{r}ava-Lifshitz gravity.
It is shown that the projective measurements made by Bob who locates near the event horizon of the Schwarzschild black hole will create entangled particles detected by Alice who stays stationary at the asymptotically flat region. It is found that the
degree of entanglement decreases as the frequency of the detected particles increases and approaches to zero as the frequency $omega_mathbf{k} toinfty$. It is also noted that the degree of entanglement increases as the Hawking temperature increases. Especially, the particle state is unentangled when the Hawking temperature is zero and approaches a maximally entangled Bell state when the black hole evaporates completely.
The entanglement of the coupled massive scalar field in the spacetime of a Garfinkle-Horowitz-Strominger(GHS) dilaton black hole has been investigated. It is found that the entanglement does not depend on the mass of the particle and the coupling bet
ween the scalar field and the gravitational field, but it decreases as the dilaton parameter $D$ increases. It is interesting to note that in the limit of $Dto M$, corresponding to the case of an extreme black hole, the state has no longer distillable entanglement for any state parameter $alpha$, but the mutual information equals to a nonvanishing minimum value, which indicates that the total correlations consist of classical correlations plus bound entanglement in this limit.
The effect of the Hawking temperature on the entanglement and teleportation for the scalar field in a most general, static and asymptotically flat black hole with spherical symmetry has been investigated. It is shown that the same initial entanglemen
t for the state parameter $alpha$ and its normalized partners $sqrt{1-alpha^{2}}$ will be degraded by the Hawking effect with increasing Hawking temperature along two different trajectories except for the maximally entangled state. In the infinite Hawking temperature limit, corresponding to the case of the black hole evaporating completely, the state has no longer distillable entanglement for any $alpha$. It is interesting to note that the mutual information in this limit equals to just half of the initially mutual information. It has also been demonstrated that the fidelity of teleportation decreases as the Hawking temperature increases, which just indicates the degradation of entanglement.
