一个真正的Lorentz-FitzGerald收缩
A real Lorentz-FitzGerald contraction
摘要：
许多凝聚态系统在低能时的集体激发可以用满足运动方程的场来描述，这些运动方程在形式上与相对论场论的运动方程没有区别。扰动在有效场中的有限传播速度（在最简单的模型中，即声速）在这里起着光速在基础物理学中的作用。然而，这些明显的相对论性场沉浸在一个外部的牛顿世界中（凝聚态系统本身和实验室可以被认为是牛顿的，因为所有涉及的速度都比光速小得多），这提供了一个特权的坐标系，因此似乎破坏了拥有一个完美定义的相对论性涌现世界的可能性。在这篇文章中，我们问自己以下问题：在一个均匀的凝聚态介质中，是否有一种方法，内部观察者，专门处理低能量的集体现象，以检测他们的状态相对于介质的匀速运动？我们提出了一个思想实验，这个实验的基础是用准粒子建造一个迈克尔逊-莫雷干涉仪，我们证明了一个真实的洛伦兹-菲茨杰拉德收缩发生了，因此内部观察者无法发现关于它们运动的“绝对”状态的任何东西。因此，我们还表明，一个有效的，但完美定义的相对论世界可以出现在一个鱼缸世界位于牛顿（实验室）系统。这使我们反思物理学中描述的各个层次，特别是关于量子引力理论的探索。
英文摘要：
Many condensed matter systems are such that their collective excitations at low energies can be described by fields satisfying equations of motion formally indistinguishable from those of relativistic field theory. The finite speed of propagation of the disturbances in the effective fields (in the simplest models, the speed of sound) plays here the role of the speed of light in fundamental physics. However, these apparently relativistic fields are immersed in an external Newtonian world (the condensed matter system itself and the laboratory can be considered Newtonian, since all the velocities involved are much smaller than the velocity of light) which provides a privileged coordinate system and therefore seems to destroy the possibility of having a perfectly defined relativistic emergent world. In this essay we ask ourselves the following question: In a homogeneous condensed matter medium, is there a way for internal observers, dealing exclusively with the low-energy collective phenomena, to detect their state of uniform motion with respect to the medium? By proposing a thought experiment based on the construction of a Michelson-Morley interferometer made of quasi-particles, we show that a real Lorentz-FitzGerald contraction takes place, so that internal observers are unable to find out anything about their `absolute ' state of motion. Therefore, we also show that an effective but perfectly defined relativistic world can emerge in a fishbowl world situated inside a Newtonian (laboratory) system. This leads us to reflect on the various levels of description in physics, in particular regarding the quest towards a theory of quantum gravity.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
