Zeno Dynamics in Quantum Statistical Mechanics
نویسنده
چکیده
We study the quantumZeno effect in quantum statistical mechanics within the operator algebraic framework. We formulate a condition for the appearance of the effect in W -dynamical systems, in terms of the short-time behaviour of the dynamics. Examples of quantum spin systems show that this condition can be effectively applied to quantum statistical mechanical models. Further, we derive an explicit form of the Zeno generator, and use it to construct Gibbs equilibrium states for the Zeno dynamics. As a concrete example, we consider the X-Y model, for which we show that a frequent measurement at a microscopic level, e.g., a single lattice site, can produce amacroscopic effect in changing the global equilibrium.
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