Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Perturbative Effective Field Theory at Finite Density   An accurate description of nuclear matter starting from free-space nuclear
forces has been an elusive goal. The complexity of the system makes
approximations inevitable, so the challenge is to find a consistent truncation
scheme with controlled errors. Nonperturbative effective field theories could
be well suited for the task. Perturbative matching in a model calculation is
used to explore some of the issues encountered in extending effective field
theory techniques to many-body calculations.

8
The categories of this paper are: hep-ex
30
The categories of this paper are: q-alg
32
The categories of this paper are: atom-ph
9
The categories of this paper are: nlin
2
The categories of this paper are: math
5
The categories of this paper are: gr-qc
28
The categories of this paper are: alg-geom
1
The categories of this paper are: cs
16
The categories of this paper are: stat
35
The categories of this paper are: mtrl-th
15
The categories of this paper are: nucl-ex
7
The categories of this paper are: hep-th
23
The categories of this paper are: solv-int
13
The categories of this paper are: quant-ph
21
The categories of this paper are: adap-org
27
The categories of this paper are: comp-gas