Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the effective action of local composite fields   The gauge invariant method for calculation of the effective action of the
local composite fields in QFT is proposed. The effective action of the local
composite fields in QED is studied up to 2-loop level. The graph rules for the
local composite fields are derived. On the basis of these rules the problem of
one-particle irreducibility is discussed.

28
The categories of this paper are: alg-geom
16
The categories of this paper are: stat
1
The categories of this paper are: cs
8
The categories of this paper are: hep-ex
21
The categories of this paper are: adap-org
11
The categories of this paper are: hep-lat
27
The categories of this paper are: comp-gas
23
The categories of this paper are: solv-int
25
The categories of this paper are: patt-sol
20
The categories of this paper are: acc-phys
9
The categories of this paper are: nlin
19
The categories of this paper are: eess
31
The categories of this paper are: ao-sci
14
The categories of this paper are: math-ph
12
The categories of this paper are: nucl-th
10
The categories of this paper are: q-bio