Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spectral and scattering theory for topological crystals perturbed by
  infinitely many new edges   In this paper we investigate the spectral and scattering theory for operators
acting on topological crystals and on their perturbations. A special attention
is paid to perturbations obtained by the addition of an infinite number of
edges, and / or by the removal of a finite number of them, but perturbations of
the underlying measures and perturbations by the addition of a multiplication
operator are also considered. The description of the nature of the spectrum of
the resulting operators, and the existence and completeness of the wave
operators are standard outcomes for these investigations.

29
The categories of this paper are: funct-an
24
The categories of this paper are: dg-ga
10
The categories of this paper are: q-bio
25
The categories of this paper are: patt-sol
32
The categories of this paper are: atom-ph
12
The categories of this paper are: nucl-th
6
The categories of this paper are: astro-ph
7
The categories of this paper are: hep-th
34
The categories of this paper are: chem-ph
11
The categories of this paper are: hep-lat
26
The categories of this paper are: bayes-an
21
The categories of this paper are: adap-org
15
The categories of this paper are: nucl-ex
0
The categories of this paper are: hep-ph
27
The categories of this paper are: comp-gas
33
The categories of this paper are: plasm-ph