Our understanding of processes occurring in the heliosphere historically began with reduced dimensionality - one-dimensional (1D) and two-dimensional (2D) sketches and models, which aimed to illustrate views on large-scale structures in the solar wind. However, any reduced dimensionality vision of the heliosphere limits the possible interpretations of in-situ observations. Accounting for non-planar structures, e.g. current sheets, magnetic islands, flux ropes as well as plasma bubbles, is decisive to shed the light on a variety of phenomena, such as particle acceleration and energy dissipation. In part I of this review, we have described in detail the ubiquitous and multi-scale observations of these magnetic structures in the solar wind and their significance for the acceleration of charged particles. Here, in part II, we elucidate existing theoretical paradigms of the structure of the solar wind and the interplanetary magnetic field, with particular attention to the fine structure and stability of current sheets. Differences in 2D and 3D views of processes associated with current sheets, magnetic islands and flux ropes are discussed. We finally review the results of numerical simulations and in-situ observations, pointing out the complex nature of magnetic reconnection and particle acceleration in a strongly turbulent environment.

历史上，我们对日光层中发生的过程的了解始于降低的维度-一维（1D）和二维（2D）草图和模型，其目的是说明有关太阳风中大型结构的观点。但是，对日球的任何缩小的维数视野都限制了对原位的可能解释观察。考虑非平面结构，例如电流板，磁岛，磁通绳以及等离子气泡，对于将各种现象（例如粒子加速和能量耗散）揭示出来是决定性的。在这篇综述的第一部分中，我们详细描述了太阳风中这些磁性结构的普遍存在和多尺度观测，以及它们对带电粒子加速的重要性。在这里，在第二部分中，我们阐明了太阳风和行星际磁场的结构的现有理论范式，特别关注了电流板的精细结构和稳定性。讨论了与电流表，磁岛和磁通绳相关的过程在2D和3D视图中的差异。最后，我们回顾了数值模拟的结果，并现场观察，指出了在强烈湍流环境中磁重联和粒子加速的复杂性。