Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: An accurate spectral method for solving the Schroedinger equation   The solution of the Lippman-Schwinger (L-S) integral equation is equivalent
to the the solution of the Schroedinger equation. A new numerical algorithm for
solving the L-S equation is described in simple terms, and its high accuracy is
confirmed for several physical situations. They are: the scattering of an
electron from a static hydrogen atom in the presence of exchange, the
scattering of two atoms at ultra low temperatures, and barrier penetration in
the presence of a resonance for a Morse potential. A key ingredient of the
method is to divide the radial range into partitions, and in each partition
expand the solution of the L-S equation into a set of Chebyshev polynomials.
The expansion is called "spectral" because it converges rapidly to high
accuracy. Properties of the Chebyshev expansion, such as rapid convergence, are
illustrated by means of a simple example.

34
The categories of this paper are: chem-ph
26
The categories of this paper are: bayes-an
31
The categories of this paper are: ao-sci
35
The categories of this paper are: mtrl-th
1
The categories of this paper are: cs
33
The categories of this paper are: plasm-ph
12
The categories of this paper are: nucl-th
14
The categories of this paper are: math-ph
13
The categories of this paper are: quant-ph
21
The categories of this paper are: adap-org
6
The categories of this paper are: astro-ph
18
The categories of this paper are: econ
5
The categories of this paper are: gr-qc
8
The categories of this paper are: hep-ex
28
The categories of this paper are: alg-geom
19
The categories of this paper are: eess