Villois Alberto, Proment Davide, Krstulovic Giorgio
Department of Physics, University of Bath, Bath BA2 7AY, United Kingdom and School of Mathematics, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, United Kingdom.
School of Mathematics, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, United Kingdom.
Phys Rev Lett. 2020 Oct 16;125(16):164501. doi: 10.1103/PhysRevLett.125.164501.
We statistically study vortex reconnections in quantum fluids by evolving different realizations of vortex Hopf links using the Gross-Pitaevskii model. Despite the time reversibility of the model, we report clear evidence that the dynamics of the reconnection process is time irreversible, as reconnecting vortices tend to separate faster than they approach. Thanks to a matching theory devised concurrently by Proment and Krstulovic [Phys. Rev. Fluids 5, 104701 (2020)PLFHBR2469-990X10.1103/PhysRevFluids.5.104701], we quantitatively relate the origin of this asymmetry to the generation of a sound pulse after the reconnection event. Our results have the prospect of being tested in several quantum fluid experiments and, theoretically, may shed new light on the energy transfer mechanisms in both classical and quantum turbulent fluids.
我们使用格罗斯-皮塔耶夫斯基模型，通过演化涡旋霍普夫链的不同实现方式，对量子流体中的涡旋重连进行了统计研究。尽管该模型具有时间可逆性，但我们报告了明确的证据，表明重连过程的动力学是时间不可逆的，因为重连的涡旋分离速度往往比重连时接近的速度更快。得益于普罗门特和克尔斯特洛维奇同时提出的匹配理论[《物理评论流体》5, 104701 (2020)PLFHBR2469-990X10.1103/PhysRevFluids.5.104701]，我们定量地将这种不对称性的起源与重连事件后声脉冲的产生联系起来。我们的结果有望在多个量子流体实验中得到验证，并且从理论上讲，可能为经典和量子湍流流体中的能量转移机制提供新的见解。
