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On the non-V-representability of currents in time-dependent many particle systems

Roberto D'Agosta·Giovanni Vignale
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Abstract

We argue that an arbitrarily chosen time-dependent current density is generically non-Vrepresentable in a many-particle system, i.e., it cannot be obtained by applying only a time dependent scalar potential to the system. Furthermore we show by a concrete example that even a current that is V-representable in an interacting many-particle system may (and in general will) turn out to be non-V-representable when the interaction between the particles is turned off.

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Roberto D'Agosta, Giovanni Vignale. 2005-01-10. On the non-V-representability of currents in time-dependent many particle systems. https://doi.org/10.1103/physrevb.71.245103

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