标题： 超流体中关联函数的图解方法 显示英文标题

标题： A diagrammatic approach to correlation functions in superfluids

摘要： 雷诺·帕伦塔尼在引力类比模型的发展方面做出了巨大贡献，这些模型被用作探索广义相对论和弯曲时空中的量子场论中各种重要方面的工具。 在这些系统中，两点关联函数对于表征接近声学视界处发生的物理过程至关重要。 本文献给他，我们研究了路径积分方法，该方法允许通过微扰展开来确定两点关联函数，这种方法不仅具有普适性，而且特别适合分析这些过程。 我们的结果适用于非相对论超流体（可以在地面实验中实现）以及相对论超流体（与致密星体相关）。 显示英文摘要

摘要： Renaud Parentani has given a vast contribution to the development of gravitational analogue models as tools to explore various important aspects of general relativity and of quantum field theory in curved space-time. In these systems, two-point correlation functions are of the utmost importance for the characterization of processes taking place close to the acoustic horizon. In the present paper, dedicated to him, we present a study of path integral methods that allow to determine two-point correlation functions by a perturbative expansion, in a way that -- beyond its generality -- is especially suited to analyze these processes. Our results apply to non-relativistic superfluids, realizable in terrestrial experiments, as well as to relativistic superfluids, relevant for compact stellar objects.