We present conditional probability (CP) density functional theory (DFT) as a formally exact theory. In essence, CP-DFT determines the ground-state energy of a system by finding the CP density from a series of independent Kohn-Sham (KS) DFT calculations. By directly calculating CP densities, we bypass the need for an approximate XC energy functional. In this paper we discuss and derive several key properties of the CP density and corresponding CP-KS potential. Illustrative examples are used throughout to help guide the reader through the various concepts and theory presented. We explore a suitable CP-DFT approximation and discuss exact conditions, limitations, and results for selected examples.

中文翻译：

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条件概率密度泛函理论

我们提出条件概率 (CP) 密度泛函理论 (DFT) 作为形式上精确的理论。本质上，CP-DFT 通过从一系列独立的 Kohn-Sham (KS) DFT 计算中找到 CP 密度来确定系统的基态能量。通过直接计算 CP 密度，我们绕过了对近似 XC 能量泛函的需求。在本文中，我们讨论并推导了 CP 密度和相应 CP-KS 势的几个关键特性。通篇使用说明性示例来帮助引导读者了解所提出的各种概念和理论。我们探索合适的 CP-DFT 近似，并讨论选定示例的确切条件、限制和结果。