Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Persistence under Weak Disorder of AC Spectra of Quasi-Periodic
  Schroedinger operators on Trees Graphs   We consider radial tree extensions of one-dimensional quasi-periodic
Schroedinger operators and establish the stability of their absolutely
continuous spectra under weak but extensive perturbations by a random
potential. The sufficiency criterion for that is the existence of Bloch-Floquet
states for the one dimensional operator corresponding to the radial problem.

35
The categories of this paper are: mtrl-th
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The categories of this paper are: chem-ph
36
The categories of this paper are: cmp-lg
8
The categories of this paper are: hep-ex
16
The categories of this paper are: stat
7
The categories of this paper are: hep-th
37
The categories of this paper are: supr-con
32
The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc
28
The categories of this paper are: alg-geom
9
The categories of this paper are: nlin
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The categories of this paper are: ao-sci
0
The categories of this paper are: hep-ph
30
The categories of this paper are: q-alg
27
The categories of this paper are: comp-gas
10
The categories of this paper are: q-bio