Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On $(\lambda,\mu)$-classes on the Engel group   The purpose of this note is to compare the properties of the symbolic
pseudo-differential calculus on the Heisenberg and on the Engel groups;
nilpotent Lie groups of 2-step and 3-step, respectively. Here we provide a
preliminary analysis of the structure and of the symbolic calculus with symbols
parametrized by $(\lambda,\mu)$ on the Engel group, while for the case of the
Heisenberg group we recall the analogous results on the $\lambda$-classes of
symbols.

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The categories of this paper are: nlin
35
The categories of this paper are: mtrl-th
3
The categories of this paper are: physics
33
The categories of this paper are: plasm-ph
37
The categories of this paper are: supr-con
4
The categories of this paper are: cond-mat
25
The categories of this paper are: patt-sol
1
The categories of this paper are: cs
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The categories of this paper are: bayes-an
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The categories of this paper are: q-bio
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The categories of this paper are: ao-sci
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The categories of this paper are: solv-int
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The categories of this paper are: chao-dyn
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The categories of this paper are: hep-th
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The categories of this paper are: nucl-th
32
The categories of this paper are: atom-ph