Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A density functional perspective for one-particle systems   Density functional theory is discussed in the context of one-particle
systems. We show that the ground state density $\rho_0(x)$ and energy $E_0$ are
simply related to a family of external potential energy functions with ground
state wave functions $\psi_n(x) \propto \rho_0(x)^n$ and energies $E_n=2nE_0$
for certain integer values of $n$.

31
The categories of this paper are: ao-sci
27
The categories of this paper are: comp-gas
18
The categories of this paper are: econ
15
The categories of this paper are: nucl-ex
25
The categories of this paper are: patt-sol
34
The categories of this paper are: chem-ph
6
The categories of this paper are: astro-ph
14
The categories of this paper are: math-ph
30
The categories of this paper are: q-alg
23
The categories of this paper are: solv-int
0
The categories of this paper are: hep-ph
36
The categories of this paper are: cmp-lg
12
The categories of this paper are: nucl-th
2
The categories of this paper are: math
3
The categories of this paper are: physics
11
The categories of this paper are: hep-lat