Title: Measures of macroscopicity for quantum spin systems
Abstract: We investigate the notion of 'macroscopicity' in the case of quantum spin systems and provide two main results. Firstly, we motivate the quantum Fisher information as a measure of the macroscopicity of quantum states. Secondly, we make a comparison with the existing literature on this topic. We report on a hierarchy among the measures and we conclude that one should carefully distinguish between 'macroscopic quantum states' and 'macroscopic superpositions', which is a strict subclass of the former.