Given a vector space of microscopic quantum observables, density functional theory is formulated on its dual space. A generalized Hohenberg-Kohn theorem and the existence of the universal energy functional in the dual space are proven. In this context ordinary density functional theory corresponds to the space of one-body multiplication operators. When the operators close under commutation to f...

The main goal of this paper is to propose an approach inverse spectral problems for functional-differential operators (FDO) with involution. For definiteness, we focus on the second-order FDO involution-reflection. Our based reduction problem matrix form and solution Sturm-Liouville operator by developing method mappings. obtained contains weight, which causes qualitative difficulties in study ...

Online media publish journalistic products, one of which is news online (online news). This in line with the findings Ministry Communication and Informatics (Kemkominfo), that 2018 there were 43,000 Indonesia. On generally getting actual news, humans tend to read on by one. The activity not effective because produced have same information each other news. In this study, we propose an innovative...