Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Outstanding problems in the phenomenology of hard diffractive scattering   This paper is a summary of the discussion within the Diffractive and Low-x
Physics Working Group at the 1999 Durham Collider Workshop of the
interpretation of the Tevatron and HERA measurements of inclusive hard
diffraction.

1
The categories of this paper are: cs
27
The categories of this paper are: comp-gas
13
The categories of this paper are: quant-ph
12
The categories of this paper are: nucl-th
24
The categories of this paper are: dg-ga
31
The categories of this paper are: ao-sci
28
The categories of this paper are: alg-geom
29
The categories of this paper are: funct-an
14
The categories of this paper are: math-ph
9
The categories of this paper are: nlin
15
The categories of this paper are: nucl-ex
7
The categories of this paper are: hep-th
18
The categories of this paper are: econ
17
The categories of this paper are: q-fin
5
The categories of this paper are: gr-qc
10
The categories of this paper are: q-bio