In this review we will focus on a topic of fundamental importance for both astrophysics and plasma physics, namely the occurrence of large-amplitude low-frequency fluctuations of the fields that describe the plasma state. This subject will be treated within the context of the expanding solar wind and the most meaningful advances in this research field will be reported emphasizing the results obtained in the past decade or so. As a matter of fact, Helios inner heliosphere and Ulysses’ high latitude observations, recent multi-spacecrafts measurements in the solar wind (Cluster four satellites) and new numerical approaches to the problem, based on the dynamics of complex systems, brought new important insights which helped to better understand how turbulent fluctuations behave in the solar wind. In particular, numerical simulations within the realm of magnetohydrodynamic (MHD) turbulence theory unraveled what kind of physical mechanisms are at the basis of turbulence generation and energy transfer across the spectral domain of the fluctuations. In other words, the advances reached in these past years in the investigation of solar wind turbulence now offer a rather complete picture of the phenomenological aspect of the problem to be tentatively presented in a rather organic way.

中文翻译：

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太阳风作为湍流实验室

在这篇综述中，我们将集中讨论一个对天体物理学和等离子体物理学都至关重要的主题，即描述等离子体状态的场的大幅度低频波动的发生。将在不断扩大的太阳风的背景下处理这个问题，并将报告该研究领域中最有意义的进展，强调在过去十年左右的时间里取得的成果。事实上，Helios的内部太阳圈和尤利西斯（Ulysses）的高纬度观测结果，最近在太阳风中进行的多航天器测量（包括四颗卫星）以及基于复杂系统动力学的新的数值方法都带来了新的重要见解这有助于更好地了解太阳风中湍流的波动行为。尤其是，磁流体动力学（MHD）湍流理论领域内的数值模拟揭示了湍流产生和整个波动谱域能量转移的基础是哪种物理机制。换句话说，过去几年在太阳风湍流研究中取得的进展现在提供了关于问题的现象学方面的相当完整的图片，将以一种较为有机的方式尝试性地提出。