标题： 混乱环 显示英文标题

标题： Scramblon loops

摘要： 在大型$N$混沌量子系统中，蝴蝶效应由一种称为“纠缠子”的集体场模介导。 我们研究了萨奇德-叶-基塔耶夫模型变体中纠缠子的自相互作用。 在该模型的空间扩展版本中，对于大空间分离情况，由环图描述的涨落可以在其对时间序以外关联函数的贡献达到一阶之前就破坏单个纠缠子近似。 我们发现，在高温（或模型的布朗版本）下的非相干区域和低温下的相干区域之间存在定性差异。 显示英文摘要

摘要： In large $N$ chaotic quantum systems, the butterfly effect is mediated by a collective field mode known as the ``scramblon.'' We study self-interactions of the scramblon in variants of the Sachdev-Ye-Kitaev model. In spatially extended versions of the model and for large spatial separation, fluctuations described by loop diagrams can invalidate the single-scramblon approximation well before its contribution to out-of-time-order correlators becomes of order one. We find a qualitative difference between an incoherent regime at high temperaure (or in a Brownian version of the model) and a coherent regime at low temperature.