Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Solenoid configurations and gravitational free energy of the AdS--Melvin
  spacetime   In this paper we explore a solenoid configuration involving a magnetic
universe solution embedded in an empty Anti-de Sitter (AdS) spacetime. This
requires a non-trivial surface current at the interface between the two
spacetimes which can be provided by a charged scalar field. When the interface
is taken to the AdS boundary, we recover the full AdS--Melvin spacetime. The
stability of the AdS--Melvin solution is also studied by computing the
gravitational free energy from the Euclidean action.

17
The categories of this paper are: q-fin
18
The categories of this paper are: econ
31
The categories of this paper are: ao-sci
0
The categories of this paper are: hep-ph
23
The categories of this paper are: solv-int
9
The categories of this paper are: nlin
16
The categories of this paper are: stat
35
The categories of this paper are: mtrl-th
29
The categories of this paper are: funct-an
22
The categories of this paper are: chao-dyn
8
The categories of this paper are: hep-ex
34
The categories of this paper are: chem-ph
33
The categories of this paper are: plasm-ph
15
The categories of this paper are: nucl-ex
1
The categories of this paper are: cs
11
The categories of this paper are: hep-lat