Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Two-dimensional Time-dependent Point Interactions   We study the time-evolution of a quantum particle subjected to time-dependent
zero-range forces in two dimensions. After establishing a conceivable ansatz
for the solution to the Schr\"{o}dinger equation, we prove that the wave packet
time-evolution is completely specified by the solutions of a system of
Volterra-type equations -- the {\it charge equations} -- involving the
coefficients of the singular part of the wave function, thus extending to the
two-dimensional case known results in one and three dimensions.

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The categories of this paper are: hep-ex
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The categories of this paper are: cond-mat
18
The categories of this paper are: econ
25
The categories of this paper are: patt-sol
6
The categories of this paper are: astro-ph
28
The categories of this paper are: alg-geom
16
The categories of this paper are: stat
34
The categories of this paper are: chem-ph
11
The categories of this paper are: hep-lat
22
The categories of this paper are: chao-dyn
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The categories of this paper are: nlin
27
The categories of this paper are: comp-gas
19
The categories of this paper are: eess
15
The categories of this paper are: nucl-ex
20
The categories of this paper are: acc-phys
31
The categories of this paper are: ao-sci