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تسجيل مستخدم جديدTime-dependent Greens functions approach to nuclear reactions
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Nonequilibrium Greens functions represent underutilized means of studying the time evolution of quantum many-body systems. In view of a rising computer power, an effort is underway to apply the Greens functions formalism to the dynamics of central nuclear reactions. As the first step, mean-field evolution for the density matrix for colliding slabs is studied in one dimension. The strategy to extend the dynamics to correlations is described.
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Linear response functions are calculated for symmetric nuclear matter of normal density by time-evolving two-time Greens functions with conserving self-energy insertions, thereby satisfying the energy-sum rule. Nucleons are regarded as moving in a me
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Linear density response functions are calculated for symmetric nuclear matter of normal density by time-evolving two-time Greens functions in real time. Of particular interest is the effect of correlations. The system is therefore initially time-evol
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I review the application of self-consistent Greens functions methods to study the properties of infinite nuclear systems. Improvements over the last decade, including the consistent treatment of three-nucleon forces and the development of extrapolati
on methods from finite to zero temperature, have allowed for realistic predictions of the equation of state of infinite symmetric, asymmetric and neutron matter based on chiral interactions. Microscopic properties, like momentum distributions or spectral functions, are also accessible. Using an indicative set of results based on a subset of chiral interactions, I summarise here the first-principles description of infinite nuclear system provided by Greens functions techniques, in the context of several issues of relevance for nuclear theory including, but not limited to, the role of short-range correlations in nuclear systems, nuclear phase transitions and the isospin dependence of nuclear observables.
Basic issues of the time-dependent density-functional theory are discussed, especially on the real-time calculation of the linear response functions. Some remarks on the derivation of the time-dependent Kohn-Sham equations and on the numerical methods are given.
We present calculations for symmetric nuclear matter using chiral nuclear interactions within the Self-Consistent Greens Functions approach in the ladder approximation. Three-body forces are included via effective one-body and two-body interactions,
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