Orbital-Free Quasi-Density Functional Theory

• URL: http://arxiv.org/abs/2304.09056v3
• Date: Wed, 7 Jun 2023 19:38:41 GMT
• Title: Orbital-Free Quasi-Density Functional Theory
• Authors: Carlos L. Benavides-Riveros
• Abstract summary: Wigner functions are broadly used to probe non-classical effects in the macroscopic world. We develop an orbital-free functional framework to compute the 1-body Wigner quasi-probability for both fermionic and bosonic systems.
• Score: 0.0
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: Wigner functions are broadly used to probe non-classical effects in the macroscopic world. Here we develop an orbital-free functional framework to compute the 1-body Wigner quasi-probability for both fermionic and bosonic systems. Since the key variable is a quasi-density, this theory is particularly well suited to circumvent the problem of finding the Pauli potential or approximating the kinetic energy in orbital-free density functional theory. As proof of principle, we find that the universal functional for the building block of optical lattices results from a translation, a contraction, and a rotation of the corresponding functional of the 1-body reduced density matrix, indicating a strong connection between these functional theories. Furthermore, we relate the concepts of Wigner negativity and $v$-representability, and find a manifold of ground states with negative Wigner functions.

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