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Criteria for two distinguishable fermions to behave like a boson

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 Publication date 2011
  fields Physics
and research's language is English




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We study the necessary conditions for bosons composed of two distinguishable fermions to exhibit bosonic-like behaviour. We base our analysis on tools of quantum information theory such as entanglement and the majorization criterion for probability distributions. In particular we scrutinize a recent interesting hypothesis by C. K. Law in the Ref. Phys. Rev. A 71, 034306 (2005) that suggests that the amount of entanglement between the constituent fermions is related to the bosonic properties of the composite boson. We show that a large amount of entanglement does not necessarily imply a good boson-like behaviour by constructing an explicit counterexample. Moreover, we identify more precisely the role entanglement may play in this situation.



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