Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Superradiance Startup at Finite Temperatures of the Electromagnetic
  Field   We use quantum-electrodynamical approach to study the initial stage of Dicke
superradiance from a system of two-level atoms. Applying the zeroth-order
Magnus approximation, we obtain the expression for the mean number of quanta
emitted in the presence of thermal fluctuations of the electromagnetic field.

24
The categories of this paper are: dg-ga
35
The categories of this paper are: mtrl-th
31
The categories of this paper are: ao-sci
11
The categories of this paper are: hep-lat
18
The categories of this paper are: econ
37
The categories of this paper are: supr-con
27
The categories of this paper are: comp-gas
33
The categories of this paper are: plasm-ph
22
The categories of this paper are: chao-dyn
7
The categories of this paper are: hep-th
1
The categories of this paper are: cs
6
The categories of this paper are: astro-ph
17
The categories of this paper are: q-fin
12
The categories of this paper are: nucl-th
34
The categories of this paper are: chem-ph
26
The categories of this paper are: bayes-an