Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Understanding Hawking radiation from simple models of atomic
  Bose-Einstein condensates   This chapter is an introduction to the Bogoliubov theory of dilute Bose
condensates as applied to the study of the spontaneous emission of phonons in a
stationary condensate flowing at supersonic speeds. This emission process is a
condensed-matter analog of Hawking radiation from astrophysical black holes but
is derived here from a microscopic quantum theory of the condensate without any
use of the analogy with gravitational systems. To facilitate physical
understanding of the basic concepts, a simple one-dimensional geometry with a
stepwise homogenous flow is considered which allows for a fully analytical
treatment.

10
The categories of this paper are: q-bio
8
The categories of this paper are: hep-ex
28
The categories of this paper are: alg-geom
35
The categories of this paper are: mtrl-th
23
The categories of this paper are: solv-int
36
The categories of this paper are: cmp-lg
18
The categories of this paper are: econ
21
The categories of this paper are: adap-org
24
The categories of this paper are: dg-ga
37
The categories of this paper are: supr-con
30
The categories of this paper are: q-alg
27
The categories of this paper are: comp-gas
22
The categories of this paper are: chao-dyn
9
The categories of this paper are: nlin
34
The categories of this paper are: chem-ph
29
The categories of this paper are: funct-an