Fundamental materials properties are determined by electrons under the potential energy from the nuclei, the electron mass, and their mutual repulsion. The variable from material to material is the ion potential. The logical procedure of computing electronic properties is to go from the potential to the electron distribution. This enables practical computation of the material properties ranging from atoms and molecules to solids. This method has blossomed due to the effort of numerous people. The concept is analogous to changing prediction of human population distribution from the landscape of hills and dales to determination of the landscape from a population distribution. In atomic systems, quantum quirkiness allows this switch, but dictates that it is only one slice in the tomography of the quantum state. The author shares his experience in the development from this slice, but hews close to the powerful concept of switching the landscape with the population.

基本材料的特性由处于原子核势能下的电子，电子质量及其相互排斥来确定。材料之间的变量是离子电势。计算电子特性的逻辑过程是从电势到电子分布。这使从原子，分子到固体的材料特性的实际计算成为可能。由于许多人的努力，这种方法得到了发展。该概念类似于将人类从山丘和山谷的景观人口分布预测转变为从人口分布确定景观的预测。在原子系统中，量子古怪性允许这种转换，但指示它只是量子状态层析成像中的一个切片。