Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Equivalent constructions of nilpotent quadratic Lie algebras   The double extension and the T*-extension are classical methods for
constructing finite dimensional quadratic Lie algebras. The first one gives an
inductive classification in characteristic zero, while the latest produces
quadratic non-associative algebras (not only Lie) out of arbitrary ones in
characteristic different from 2. The classification of quadratic nilpotent Lie
algebras can also be reduced to the study of free nilpotent Lie algebras and
their invariant forms. In this work we will establish an equivalent
characterization among these three construction methods. This equivalence
reduces the classification of quadratic 2-step nilpotent to that of trivectors
in a natural way. In addition, theoretical results will provide simple rules
for switching among them.

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The categories of this paper are: adap-org
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The categories of this paper are: econ
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The categories of this paper are: acc-phys
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The categories of this paper are: cs
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The categories of this paper are: chem-ph
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The categories of this paper are: hep-ex
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The categories of this paper are: alg-geom
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The categories of this paper are: gr-qc
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The categories of this paper are: cmp-lg
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The categories of this paper are: quant-ph
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The categories of this paper are: nlin
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The categories of this paper are: nucl-ex
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The categories of this paper are: q-alg
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The categories of this paper are: eess
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The categories of this paper are: comp-gas
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The categories of this paper are: ao-sci