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Existence of A Rigorous Density-Functional Theory for Open Electronic Systems

Xiao Zheng·Fan Wang·GuanHua Chen
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Abstract

We prove that the electron density function of a real physical system can be uniquely determined by its values on any finite subsystem. This establishes the existence of a rigorous density-functional theory for any open electronic system. By introducing a new density functional for dissipative interactions between the reduced system and its environment, we subsequently develop a time-dependent density-functional theory which depends in principle only on the electron density of the reduced system.

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Xiao Zheng, Fan Wang, GuanHua Chen. 2006-05-11. Existence of A Rigorous Density-Functional Theory for Open Electronic Systems. https://arxiv.org/abs/quant-ph/0605104

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