Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Locally nilpotent derivations of graded integral domains and
  cylindricity   Let B be a commutative $\mathbb{Z}$-graded domain of characteristic zero. An
element f of B is said to be cylindrical if it is nonzero, homogeneous of
nonzero degree, and such that $B_{(f)}$ is a polynomial ring in one variable
over a subring. We study the relation between the existence of a cylindrical
element of B and the existence of a nonzero locally nilpotent derivation of B.
Also, given d > 0, we give sufficient conditions that guarantee that every
derivation of $B^{(d)} = \oplus_i B_{di}$ can be extended to a derivation of B.
We generalize some results of Kishimoto, Prokhorov and Zaidenberg that relate
the cylindricity of a polarized projective variety (Y,H) to the existence of a
nontrivial G_a-action on the affine cone over (Y,H).

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The categories of this paper are: astro-ph
17
The categories of this paper are: q-fin
33
The categories of this paper are: plasm-ph
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The categories of this paper are: nucl-ex
32
The categories of this paper are: atom-ph
3
The categories of this paper are: physics
16
The categories of this paper are: stat
22
The categories of this paper are: chao-dyn
25
The categories of this paper are: patt-sol
37
The categories of this paper are: supr-con
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The categories of this paper are: q-bio
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The categories of this paper are: gr-qc
34
The categories of this paper are: chem-ph
30
The categories of this paper are: q-alg
35
The categories of this paper are: mtrl-th
12
The categories of this paper are: nucl-th