Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Topological invariants for projection method patterns   We analyze and compare different dynamical systems and groupoids which can be
obtained from projection point patterns. We define the cohomology of a point
pattern as the cocycle cohomology of the pattern groupoid. We describe this
cohomology qualitatively and calculate it for canonical projection method
tilings with codimension smaller or equal than 3.

8
The categories of this paper are: hep-ex
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The categories of this paper are: q-fin
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The categories of this paper are: nlin
13
The categories of this paper are: quant-ph
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The categories of this paper are: chem-ph
18
The categories of this paper are: econ
15
The categories of this paper are: nucl-ex
30
The categories of this paper are: q-alg
1
The categories of this paper are: cs
28
The categories of this paper are: alg-geom
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The categories of this paper are: supr-con
26
The categories of this paper are: bayes-an
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The categories of this paper are: cmp-lg
12
The categories of this paper are: nucl-th
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The categories of this paper are: solv-int
11
The categories of this paper are: hep-lat