Il Nuovo Cimento B (1971-1996)

, Volume 82, Issue 2, pp 169–191 | Cite as

Quantum thermodynamics. A new equation of motion for a single constituent of matter

  • G. P. Beretta
  • E. P. Gyftopoulos
  • J. L. Park
  • G. N. Hatsopoulos


A novel nonlinear equation of motion is proposed for quantum systems consisting of a single elementary constituent of matter. It is satisfied by pure states and by a special class of mixed states evolving unitarily. But, in general, it generates a nonunitary evolution of the state operator. It keeps the energy invariant and causes the entropy to increase with time until the system reaches a state of equilibrium or a limit cycle.

PACS. 03.65. Quantum theory quantum mechanics 

Квантовая термодинамика. Новое уравнение движения для однокомпонентного вещества


Для квантовых систем, состоящих из вещества, представляюего одну элементарную компоненту, предлагается новое нелинейное уравнение движения. Уравнение удовлетворяется для чистых состояний и для специального класса смешанных состояний. В общем случае, это уравнение генерирует неунитарную эволюцию оператора состояния. Это уравнение сохраняет энергию инвариантной, вызывает увелиыение энтропии со временем, пока система не достигнет состояния равновесия.


Si propone una nuova equazione di evoluzione per sistemi quantistici composti da un singolo costituente materiale elementare. L'equazione è soddisfatta dall'evoluzione unitaria degli stati puri e di una sottoclasse di stati misti. Ma, in generale, essa genera un'evoluzione non unitaria dell'operatore di stato. L'equazione mantiene costante il valor medio dell'energia e causa aumenti di entropia finché il sistema non raggiunge uno stato di equilibrio oppure un ciclo limite.


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Copyright information

© Società Italiana di Fisica 1984

Authors and Affiliations

  • G. P. Beretta
    • 1
  • E. P. Gyftopoulos
    • 1
  • J. L. Park
    • 2
  • G. N. Hatsopoulos
    • 3
  1. 1.Massachusetts Institute of TechnologyCambridge
  2. 2.Washington State UniversityPullman
  3. 3.Thermo Electron CorporationWaltham

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