Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A Simple Derivation of the Hard Thermal Loop Effective Action   We use the background field method along with a special gauge condition, to
derive the hard thermal loop effective action in a simple manner. The new point
in the paper is to relate the effective action explicitly to the S-matrix from
the onset.

0
The categories of this paper are: hep-ph
12
The categories of this paper are: nucl-th
29
The categories of this paper are: funct-an
11
The categories of this paper are: hep-lat
27
The categories of this paper are: comp-gas
34
The categories of this paper are: chem-ph
1
The categories of this paper are: cs
19
The categories of this paper are: eess
10
The categories of this paper are: q-bio
37
The categories of this paper are: supr-con
4
The categories of this paper are: cond-mat
33
The categories of this paper are: plasm-ph
28
The categories of this paper are: alg-geom
18
The categories of this paper are: econ
8
The categories of this paper are: hep-ex
32
The categories of this paper are: atom-ph