论文标题
地平线上的Qubit：在黑洞附近的变形和热化
Qubits on the Horizon: Decoherence and Thermalization near Black Holes
论文作者
论文摘要
我们检查了值（或Unruh-de Witt检测器）的后期演变，该量子位置非常接近Schwarzschild黑洞的事件范围，同时与自由量子标量场相互作用。该计算是在无量纲的Qubit/field耦合$ g $的情况下进行的，但我们没有计算由于现场互动而引起的量子激发率（通常是这样做的），而是使用开放的EFT技术来计算$ g^2 t/r_s $ g^$ g^$ g^4 t/r r _s $ r_s $ r_s $ r_s $ r_s $ r_s $ r_s $ r_s $ r_s $ r_s $ r_s $ r_s $ r r y r_s $ r_s Schwarzschild半径。我们表明，对于足够接近地平线的量子位，后期演化采用了一种简单的通用形式，仅取决于近晶体的几何形状，只是假设量子场是在hadamard型状态（例如hartle-hawking the hartle-hawking或unruh vacua）制备的。当两个量子状态之间的红移能量差（$ω_\ indty $）（由远距离观察者衡量的探测器来衡量）满足$ω__\ iftty r_s \ ll 1 $这种普遍的进化变为马克维亚人，并描述了与霍克（Hawking）相对范围的平衡方法，并描述了一个平衡的方法，并散发出了偏离的态度。具有不同特征时间的平衡，$ r_s/g^2 $。
We examine the late-time evolution of a qubit (or Unruh-De Witt detector) that hovers very near to the event horizon of a Schwarzschild black hole, while interacting with a free quantum scalar field. The calculation is carried out perturbatively in the dimensionless qubit/field coupling $g$, but rather than computing the qubit excitation rate due to field interactions (as is often done), we instead use Open EFT techniques to compute the late-time evolution to all orders in $g^2 t/r_s$ (while neglecting order $g^4 t/r_s$ effects) where $r_s = 2GM$ is the Schwarzschild radius. We show that for qubits sufficiently close to the horizon the late-time evolution takes a simple universal form that depends only on the near-horizon geometry, assuming only that the quantum field is prepared in a Hadamard-type state (such as the Hartle-Hawking or Unruh vacua). When the redshifted energy difference, $ω_\infty$, between the two qubit states (as measured by a distant observer looking at the detector) satisfies $ω_\infty r_s \ll 1$ this universal evolution becomes Markovian and describes an exponential approach to equilibrium with the Hawking radiation, with the off-diagonal and diagonal components of the qubit density matrix relaxing to equilibrium with different characteristic times, both of order $r_s/g^2$.
