Jannes G, Piquet R, Maïssa P, Mathis C, Rousseaux G
Université de Nice Sophia Antipolis, Laboratoire J.-A. Dieudonné, UMR CNRS-UNS 6621, Parc Valrose, F-06108 Nice Cedex 02, France.
Phys Rev E Stat Nonlin Soft Matter Phys. 2011 May;83(5 Pt 2):056312. doi: 10.1103/PhysRevE.83.056312. Epub 2011 May 11.
We provide an experimental demonstration that the circular hydraulic jump represents a hydrodynamic white hole or gravitational fountain (the time reverse of a black hole) by measuring the angle of the Mach cone created by an object in the "supersonic" inner flow region. We emphasize the general character of this gravitational analogy by showing theoretically that the white hole horizon constitutes a stationary and spatial saddle-node bifurcation within dynamical-systems theory. We also demonstrate that the inner region has a "superluminal" dispersion relation, that is, that the group velocity of the surface waves increases with frequency, and discuss some possible consequences with respect to the robustness of Hawking radiation. Finally, we point out that our experiment shows a concrete example of a possible "trans-Planckian distortion" of black or white holes.
通过测量“超音速”内流区域中物体产生的马赫锥角度，我们提供了一个实验证明，即圆形水力跃变代表了一个流体动力学白洞或引力喷泉（黑洞的时间反演）。通过理论证明白洞视界在动力系统理论中构成一个静态且空间的鞍结分岔，我们强调了这种引力类比的一般性。我们还证明了内部区域具有“超光速”色散关系，即表面波的群速度随频率增加，并讨论了关于霍金辐射鲁棒性的一些可能后果。最后，我们指出我们的实验展示了黑洞或白洞可能的“跨普朗克失真”的一个具体例子。
