Coherent states statistical mechanical approach

The first volume contained nine state-of-the-art chapters on fundamental aspects, on formalism, and on a variety of applications. The various discussions employ both stationary and time-dependent frameworks, with Hermitian and non-Hermitian Hamiltonian constructions. A variety of formal and computational results address themes from quantum and statistical mechanics to the detailed analysis of time evolution of material or photon wave packets, from the difficult problem of combining advanced many-electron methods with properties of field-free and field-induced resonances to the dynamics of molecular processes and coherence effects in strong electromagnetic fields and strong laser pulses, from portrayals of novel phase space approaches of quantum reactive scattering to aspects of recent developments related to quantum information processing. 

The master equation approach has a long story tracing back to the pioneering work of Pauli [6] and van Hove [7], motivated by the need of reconciling quantum mechanical coherence with the evident randomness of statistical physics. In this section we illustrate this transition from coherent to incoherent behavior with a simple, but paradigmatic, model that will be repeatedly adopted in this review. Let us imagine a quantum system with two states, 11) and 2). The incoherent process described by the Pauli master equation is illustrated by the following set of two equations... 

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