Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Solving Dirac equations on a 3D lattice with inverse Hamiltonian and
  spectral methods   A new method to solve the Dirac equation on a 3D lattice is proposed, in
which the variational collapse problem is avoided by the inverse Hamiltonian
method and the fermion doubling problem is avoided by performing spatial
derivatives in momentum space with the help of the discrete Fourier transform,
i.e., the spectral method. This method is demonstrated in solving the Dirac
equation for a given spherical potential in 3D lattice space. In comparison
with the results obtained by the shooting method, the differences in single
particle energy are smaller than $10^{-4}$~MeV, and the densities are almost
identical, which demonstrates the high accuracy of the present method. The
results obtained by applying this method without any modification to solve the
Dirac equations for an axial deformed, non-axial deformed, and octupole
deformed potential are provided and discussed.

18
The categories of this paper are: econ
14
The categories of this paper are: math-ph
13
The categories of this paper are: quant-ph
2
The categories of this paper are: math
8
The categories of this paper are: hep-ex
7
The categories of this paper are: hep-th
3
The categories of this paper are: physics
23
The categories of this paper are: solv-int
0
The categories of this paper are: hep-ph
22
The categories of this paper are: chao-dyn
11
The categories of this paper are: hep-lat
29
The categories of this paper are: funct-an
1
The categories of this paper are: cs
6
The categories of this paper are: astro-ph
28
The categories of this paper are: alg-geom
35
The categories of this paper are: mtrl-th