Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A description of pseudo-bosons in terms of nilpotent Lie algebras   We show how the one-mode pseudo-bosonic ladder operators provide concrete
examples of nilpotent Lie algebras of dimension five. It is the first time that
an algebraic-geometric structure of this kind is observed in the context of
pseudo-bosonic operators. Indeed we don't find the well known Heisenberg
algebras, which are involved in several quantum dynamical systems, but
different Lie algebras which may be decomposed in the sum of two abelian Lie
algebras in a prescribed way. We introduce the notion of semidirect sum (of Lie
algebras) for this scope and find that it describes very well the behaviour of
pseudo-bosonic operators in many quantum models.

29
The categories of this paper are: funct-an
31
The categories of this paper are: ao-sci
12
The categories of this paper are: nucl-th
37
The categories of this paper are: supr-con
20
The categories of this paper are: acc-phys
23
The categories of this paper are: solv-int
11
The categories of this paper are: hep-lat
34
The categories of this paper are: chem-ph
30
The categories of this paper are: q-alg
27
The categories of this paper are: comp-gas
26
The categories of this paper are: bayes-an
5
The categories of this paper are: gr-qc
36
The categories of this paper are: cmp-lg
9
The categories of this paper are: nlin
22
The categories of this paper are: chao-dyn
3
The categories of this paper are: physics