Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: An equivariant pullback structure of trimmable graph C*-algebras   We prove that the graph C*-algebra $C^*(E)$ of a trimmable graph $E$ is
$U(1)$-equivariantly isomorphic to a pullback C*-algebra of a subgraph
C*-algebra $C^*(E'')$ and the C*-algebra of functions on a circle tensored with
another subgraph C*-algebra $C^*(E')$. This allows us to unravel the structure
and K-theory of the fixed-point subalgebra $C^*(E)^{U(1)}$ through the
(typically simpler) C*-algebras $C^*(E')$, $C^*(E'')$ and $C^*(E'')^{U(1)}$. As
examples of trimmable graphs, we consider one-loop extensions of the standard
graphs encoding respectively the Cuntz algebra $\mathcal{O}_2$ and the Toeplitz
algebra $\mathcal{T}$. Then we analyze equivariant pullback structures of
trimmable graphs yielding the C*-algebras of the Vaksman-Soibelman quantum
sphere $S^{2n+1}_q$ and the quantum lens space $L_q^3(l; 1,l)$, respectively.

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The categories of this paper are: hep-th
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The categories of this paper are: physics
11
The categories of this paper are: hep-lat
19
The categories of this paper are: eess
25
The categories of this paper are: patt-sol
31
The categories of this paper are: ao-sci
1
The categories of this paper are: cs
6
The categories of this paper are: astro-ph
34
The categories of this paper are: chem-ph
28
The categories of this paper are: alg-geom
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The categories of this paper are: gr-qc
29
The categories of this paper are: funct-an
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The categories of this paper are: nlin
18
The categories of this paper are: econ
0
The categories of this paper are: hep-ph
26
The categories of this paper are: bayes-an