2008/05/31 by Marcelo A. Marchiolli, Evandro C. Silva, D. Galetti +1
Physics and Astronomy · #Cold Atom Physics and Bose-Einstein Condensates #Entropy (arrow of time) #Excited state #Formalism (music) #Phase space #Physics #Quantum chaos and dynamical systems #Quantum many-body systems #Quantum mechanics #Quantum tunnelling #Statistical physics #quant-ph
paper · pdf · doi:10.1103/physreva.79.022114
7 pages, 8 figures, title modified, new setences and references included, to appear in Physical Review A
arxiv created 2009/01/25 · openalex publication_date 2009/02/17 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We show how quasiprobability distribution functions defined over N2-dimensional discrete phase spaces can be used to treat physical systems described by a finite space of states which exhibit spin-tunneling effects. This particular approach is then applied to the Lipkin-Meshkov-Glick model in order to obtain the time evolution of the discrete Husimi function, and as a by-product the energy gap for a symmetric combination of ground and first excited states. Moreover, we also show how an angle-based potential approach can be efficiently employed to explain qualitatively certain features of the energy gap in terms of a spin tunneling. Entropy functionals are also discussed in this context. Such results reinforce not only the formalism per se but also the possibility of some future potential applications in other branches of physics.