What Makes Magnetic Reconnection Stop?

We propose a new angle of attack that promises a breakthrough in this scientific challenge. Past and present research is overwhelmingly focused on the questions of how reconnection starts and how it operates after it started. The question of how it stops, in contrast, has received very little attention. This is surprising given the obvious implications hereof for the effectiveness, scale, and impact of the reconnection process on the large-scale system. For example, without knowing when and how reconnection stops, we cannot determine the energy transport into and inside of the Earth space environment, or estimate the size of a solar eruption or a stellar flare. On the most basic level, we will not know when reconnection will occur if we do not know when it cannot occur. We seek to answer this fundamental question regarding magnetic reconnection: what makes it stop? The results will provide key insights that extend far beyond the determination of when and how reconnection ceases in the magnetosphere, in the solar wind, the solar atmosphere and beyond. Many other important applications, for example in relativistic, astrophysical plasmas and fusion plasma research, will benefit from the new knowledge produced here. The goal is to develop a unified understanding of what stops reconnection, which, in turn, implies knowledge of what it needs to work. In this sense, the proposed research will also create fundamental advances in basic reconnection research.