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arXiv · 1605.04588

Comment on "On the unphysical solutions of the Kadanoff--Baym equations in linear response: Correlation-induced homogeneous density-distribution and attractors"

N. Schlünzen·J. -P. Joost·M. Bonitz
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Abstract

In a recent Rapid Communication [A. Stan, Phys. Rev. B \textbf{93}, 041103(R) (2016)], the reliability of the Keldysh--Kadanoff--Baym equations (KBE) using correlated selfenergy approximations applied to linear and nonlinear response has been questioned. In particular, the existence of a universal attractor has been predicted that would drive the dynamics of any correlated system towards an unphysical homogeneous density distribution regardless of the system type, the interaction and the many-body approximation. Moreover, it was conjectured that even the mean-field dynamics would be damped. Here, by performing accurate solutions of the KBE for situations studied in that paper, we prove these claims wrong being caused by numerical inaccuracies.

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N. Schlünzen, J. -P. Joost, M. Bonitz. 2016-11-18. Comment on "On the unphysical solutions of the Kadanoff--Baym equations in linear response: Correlation-induced homogeneous density-distribution and attractors". https://doi.org/10.1103/physrevb.96.117101

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