Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Tridiagonal Representation Approach in Quantum Mechanics   We present an algebraic approach for finding exact solutions of the wave
equation. The approach, which is referred to as the Tridiagonal Representation
Approach (TRA), is inspired by the J-matrix method and based on the theory of
orthogonal polynomials. The class of exactly solvable problems in this approach
is larger than the conventional class. All properties of the physical system
(energy spectrum of the bound states, phase shift of the scattering states,
energy density of states, etc.) are obtained in this approach directly and
simply from the properties of the associated orthogonal polynomials.

31
The categories of this paper are: ao-sci
34
The categories of this paper are: chem-ph
22
The categories of this paper are: chao-dyn
2
The categories of this paper are: math
12
The categories of this paper are: nucl-th
16
The categories of this paper are: stat
0
The categories of this paper are: hep-ph
24
The categories of this paper are: dg-ga
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The categories of this paper are: eess
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The categories of this paper are: econ
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The categories of this paper are: alg-geom
26
The categories of this paper are: bayes-an
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The categories of this paper are: atom-ph
14
The categories of this paper are: math-ph
9
The categories of this paper are: nlin
33
The categories of this paper are: plasm-ph