核流体中的声学层位
Acoustic horizons in nuclear fluids
摘要：
我们认为一个流体动力学描述的球对称向外流动的核物质，容纳分散在它作为一个非常弱的影响。关于由此产生的流动中的定常条件，我们应用欧拉方案推导出一个完全非线性方程的时间依赖的径向扰动。在其线性化的极限，没有色散，这个方程意味着静态声学地平线的模拟重力模型。然而，我们表明，随时间变化的非线性效应不稳定的静态视界。我们还将扰动建模为高频行波，并进行{ \it WKB}分析，其中迭代地研究了弱色散的影响。我们发现，即使任意小的值的色散使地平线完全不透明的任何声扰动对体积流的传播，与幅度和能量通量的径向扰动经历一个不连续的地平线上，和指数衰减就在外面。
英文摘要：
We consider a hydrodynamic description of the spherically symmetric outward flow of nuclear matter, accommodating dispersion in it as a very weak effect. About the resulting stationary conditions in the flow, we apply an Eulerian scheme to derive a fully nonlinear equation of a time-dependent radial perturbation. In its linearized limit, with no dispersion, this equation implies the static acoustic horizon of an analogue gravity model. We, however, show that time-dependent nonlinear effects destabilize the static horizon. We also model the perturbation as a high-frequency travelling wave, and perform a {\it WKB} analysis, in which the effect of weak dispersion is studied iteratively. We show that even arbitrarily small values of dispersion make the horizon fully opaque to any acoustic disturbance propagating against the bulk flow, with the amplitude and the energy flux of the radial perturbation undergoing a discontinuity at the horizon, and decaying exponentially just outside it.
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。
