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arXiv · 1312.7741

Time irreversibility in the quantum systems with infinite number of particles

Abstract

The time irreversible evolution of quantum systems with infinite number of particles (QSINP) was studied within a newly constructed algebraic framework. The QSINP could be described by the quantum infinite lattice field. The *-Algebra R is the set of all dynamic variables of the QSINP, in which a special addition and multiplication operations were defined. The full pure state vector (FPSV) \rho, the pure state vector {\rho_f} and the equivalent relations within them are also well defined. The set of all pure state vectors, which are equivalent to the FPSV \rho, is a Hilbert Space {H_\rho}, if the addition, the inner product and the norm were defined in it. The set of all linear transformation {N_\rho} on {H_\rho} is isomorphic to R, and {{N_\rho},{H_\rho}} is the representation of R, associated with \rho. The *-Algebra R has infinitely many non-equivalent irreducible GNS constructions (representations), associated with different nonequivalent FPSVs respectively. It is proved that, the dynamical motions of the QSINP is totally within the GNS construction associated with the initial pure state vector; However, the time reversal transformation makes the initial FPSV and its corresponding dynamical evolution into another non-equivalent GNS construction. Therefore, within the GNS construction associated with the FPSV, the dynamics of the QSINP is time irreversible. Finally, due to the Liouville operator has real continuous spectrum within the GNS construction, the longtime asymptotic solution of Liouville equation in the GNS construction could be treated by the formal scattering theory. The Master equation with dissipative term was obtained, which is formally irrelevant of the initial state and the corresponding GNS construction. This master equation could be regarded as the evolution equation of the QSINP on R.

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Yuping Huo. 2013-12-24. Time irreversibility in the quantum systems with infinite number of particles. https://arxiv.org/abs/1312.7741

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