Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Flavor mixing and renormalization in a perturbation theory   The renormalization of theories with flavor mixing is discussed, and it is
shown that the physical unstable particles should be interpreted as
quasiparticles which cannot be regarded as external states. Several popular
beliefs on renormalization are disproved accordingly, and the limitations of
physical renormalization schemes are discussed. In addition, the properties of
unstable particles with flavor mixing such as decay widths are studied from
scattering mediated by them.

24
The categories of this paper are: dg-ga
4
The categories of this paper are: cond-mat
27
The categories of this paper are: comp-gas
26
The categories of this paper are: bayes-an
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
12
The categories of this paper are: nucl-th
29
The categories of this paper are: funct-an
13
The categories of this paper are: quant-ph
37
The categories of this paper are: supr-con
1
The categories of this paper are: cs
31
The categories of this paper are: ao-sci
17
The categories of this paper are: q-fin
21
The categories of this paper are: adap-org
14
The categories of this paper are: math-ph