Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On derivations of parabolic Lie algebras   Let $\mathfrak{g}$ be a reductive Lie algebra over an algebraically closed,
characteristic zero field or over $\mathbb{R}$. Let $\mathfrak{q}$ be a
parabolic subalgebra of $\mathfrak{g}$. We characterize the derivations of
$\mathfrak{q}$ by decomposing the derivation algebra as the direct sum of two
ideals: one of which being the image of the adjoint representation and the
other consisting of all linear transformations on $\mathfrak{q}$ that map into
the center of $\mathfrak{q}$ and map the derived algebra of $\mathfrak{q}$ to
$0$.

27
The categories of this paper are: comp-gas
35
The categories of this paper are: mtrl-th
15
The categories of this paper are: nucl-ex
30
The categories of this paper are: q-alg
11
The categories of this paper are: hep-lat
21
The categories of this paper are: adap-org
37
The categories of this paper are: supr-con
26
The categories of this paper are: bayes-an
18
The categories of this paper are: econ
9
The categories of this paper are: nlin
14
The categories of this paper are: math-ph
7
The categories of this paper are: hep-th
16
The categories of this paper are: stat
8
The categories of this paper are: hep-ex
4
The categories of this paper are: cond-mat
23
The categories of this paper are: solv-int