Lima Cesar A Uliana, Brito Frederico, Hoyos José A, Vanzella Daniel A Turolla
Instituto de Física de São Carlos, Universidade de São Paulo, Caixa Postal 369, São Carlos, 13560-970, São Paulo, Brazil.
Nat Commun. 2019 Jul 10;10(1):3030. doi: 10.1038/s41467-019-10962-y.
It has been proved in the context of quantum fields in Minkowski spacetime that the vacuum state is a thermal state according to uniformly accelerated observers-a seminal result known as the Unruh effect. Recent claims, however, have challenged the validity of this result for extended systems, thus casting doubts on its physical reality. Here, we study the dynamics of an extended system, uniformly accelerated in the vacuum. We show that its reduced density matrix evolves to a Gibbs thermal state with local temperature given by the Unruh temperature [Formula: see text], where a is the system's spatial-dependent proper acceleration-c is the speed of light and k and [Formula: see text] are the Boltzmann's and the reduced Planck's constants, respectively. This proves that the vacuum state does induce thermalization of an accelerated extended system-which is all one can expect of a legitimate thermal reservoir.
在闵可夫斯基时空的量子场背景下已证明，对于做匀加速运动的观测者而言，真空态是一种热态——这一开创性结果被称为昂鲁效应。然而，最近有观点对该结果在扩展系统中的有效性提出了质疑，从而对其物理实在性产生了怀疑。在此，我们研究在真空中做匀加速运动的扩展系统的动力学。我们表明，其约化密度矩阵演化为具有由昂鲁温度[公式：见正文]给出的局部温度的吉布斯热态，其中a是系统依赖于空间的固有加速度，c是光速，k和[公式：见正文]分别是玻尔兹曼常数和约化普朗克常数。这证明了真空态确实会导致加速扩展系统的热化——这是一个合理的热库所能期望的全部。
