Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Fundamentality of Fields   There is debate as to whether quantum field theory is, at bottom, a quantum
theory of fields or particles. One can take a field approach to the theory,
using wave functionals over field configurations, or a particle approach, using
wave functions over particle configurations. This article argues for a field
approach, presenting three advantages over a particle approach: (1) particle
wave functions are not available for photons, (2) a classical field model of
the electron gives a superior account of both spin and self-interaction as
compared to a classical particle model, and (3) the space of field wave
functionals appears to be larger than the space of particle wave functions. The
article also describes two important tasks facing proponents of a field
approach: (1) legitimize or excise the use of Grassmann numbers for fermionic
field values and wave functional amplitudes, and (2) describe how quantum
fields give rise to particle-like behavior.

17
The categories of this paper are: q-fin
4
The categories of this paper are: cond-mat
6
The categories of this paper are: astro-ph
16
The categories of this paper are: stat
12
The categories of this paper are: nucl-th
22
The categories of this paper are: chao-dyn
27
The categories of this paper are: comp-gas
34
The categories of this paper are: chem-ph
29
The categories of this paper are: funct-an
23
The categories of this paper are: solv-int
10
The categories of this paper are: q-bio
2
The categories of this paper are: math
28
The categories of this paper are: alg-geom
9
The categories of this paper are: nlin
20
The categories of this paper are: acc-phys
8
The categories of this paper are: hep-ex