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Measures of macroscopicity for quantum spin systems

Quantum Physics 2012-09-28 v2

Abstract

We investigate the notion of "macroscopicity" in the case of large quantum spin systems and provide two main results. First, we motivate the Fisher information as a measure for the macroscopicity of quantum states. Second, we compare the existing literature of 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.

Keywords

Cite

@article{arxiv.1205.3048,
  title  = {Measures of macroscopicity for quantum spin systems},
  author = {Florian Fröwis and Wolfgang Dür},
  journal= {arXiv preprint arXiv:1205.3048},
  year   = {2012}
}

Comments

Comments are welcome! v2: Minor improvements of the text

R2 v1 2026-06-21T21:03:30.901Z