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arXiv · 2609.08983

Time-Dependent Density Functional Theory with Coulomb Interactions

Asbjørn Bækgaard Lauritsen·Mathieu Lewin·Jakob Oldenburg
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Abstract

We provide the first fully rigorous justification of time-dependent density functional theory in the continuum: Given a time-dependent density, we prove that there exists an external potential, unique up to a time-dependent constant, such that the corresponding Schr\"odinger equation reproduces the given density. This potential can be obtained with an iteration scheme. Our argument covers Coulomb interactions and does not need any Taylor expansion in time. It instead requires analyticity in space for the density and potential, which is compatible with extended nuclei.

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Asbjørn Bækgaard Lauritsen, Mathieu Lewin, Jakob Oldenburg. 2026-09-08. Time-Dependent Density Functional Theory with Coulomb Interactions. https://arxiv.org/abs/2609.08983

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