论文标题
来自纺丝中的非层次戈德石模式的模拟空间
Analog spacetimes from nonrelativistic Goldstone modes in spinor condensates
论文作者
论文摘要
众所周知,流动量子流体中的线性分散模式的表现似乎是耦合到爱因斯坦 - 希尔伯特度量标准的耦合,并且在弯曲空间(包括鹰辐射)中表现出来自量子场理论的许多现象。我们将这种类比扩展到流动的纺纱玻璃酿造液中的任何非层压巨石模式。除了显示所有这些模式的线性色散结果外,我们还表明,四边形分散模式将夫妇融合到一个特殊的非层次时空时期,称为牛顿 - 卡丹几何形状。那种时空(爱因斯坦 - 希尔伯特或牛顿 - 卡丹)与冷凝水的平均场相密切相关。为了说明总体结果,我们在伪自动1/2凝结物的背景下进一步提供了特定的理论,我们可以在相对论和非依赖主义的几何形状之间进行调节。我们在这种过渡时发现了鹰辐射的命运:尽管任何流体流都为某些波数创造了地平线,但它在牛顿 - 卡丹几何几何形状中仍然没有。最后,我们使用与不同的空间耦合来计算和关联这些模拟系统中的各种能量和动量电流。尽管此结果是一般的,但当今的实验可以实现这些不同的空间,包括$^{87} $ rb,$^{7} $ li,$^{41} $ k(newton-cartan)和$^{23} $ na(einstein-hilbert)等自旋-1凝结物的磁通模式。
It is well established that linear dispersive modes in a flowing quantum fluid behave as though they are coupled to an Einstein-Hilbert metric and exhibit a host of phenomena coming from quantum field theory in curved space, including Hawking radiation. We extend this analogy to any nonrelativistic Goldstone mode in a flowing spinor Bose-Einstein condensate. In addition to showing the linear dispersive result for all such modes, we show that the quadratically dispersive modes couple to a special nonrelativistic spacetime called a Newton-Cartan geometry. The kind of spacetime (Einstein-Hilbert or Newton-Cartan) is intimately linked to the mean-field phase of the condensate. To illustrate the general result, we further provide the specific theory in the context of a pseudo-spin-1/2 condensate where we can tune between relativistic and nonrelativistic geometries. We uncover the fate of Hawking radiation upon such a transition: it vanishes and remains absent in the Newton-Cartan geometry despite the fact that any fluid flow creates a horizon for certain wave numbers. Finally, we use the coupling to different spacetimes to compute and relate various energy and momentum currents in these analog systems. While this result is general, present day experiments can realize these different spacetimes including the magnon modes for spin-1 condensates such as $^{87}$Rb, $^{7}$Li, $^{41}$K (Newton-Cartan), and $^{23}$Na (Einstein-Hilbert).