Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Ambiguities in the definition of local spatial densities in light
  hadrons   The relationship between the matrix element of a local operator and the
Fourier transform of the associated form factor fails for systems such as the
nucleon where its intrinsic size is of order its Compton wavelength. Although
one can conceive of an intrinsic charge density distribution in the proton,
there does not seem to be an unambiguous way to define, compute, or measure it
precisely.

30
The categories of this paper are: q-alg
21
The categories of this paper are: adap-org
1
The categories of this paper are: cs
29
The categories of this paper are: funct-an
25
The categories of this paper are: patt-sol
36
The categories of this paper are: cmp-lg
19
The categories of this paper are: eess
26
The categories of this paper are: bayes-an
6
The categories of this paper are: astro-ph
20
The categories of this paper are: acc-phys
28
The categories of this paper are: alg-geom
35
The categories of this paper are: mtrl-th
14
The categories of this paper are: math-ph
10
The categories of this paper are: q-bio
2
The categories of this paper are: math
5
The categories of this paper are: gr-qc