Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum interference with distinguishable photons through
  indistinguishable pathways   We report a two-photon interference experiment in which the detected photons
have very different properties. The interference is observed even when no
effort is made to mask the distinguishing features before the photons are
detected. The results can only be explained in terms of indistinguishable
two-photon amplitudes.

9
The categories of this paper are: nlin
17
The categories of this paper are: q-fin
5
The categories of this paper are: gr-qc
14
The categories of this paper are: math-ph
30
The categories of this paper are: q-alg
25
The categories of this paper are: patt-sol
3
The categories of this paper are: physics
27
The categories of this paper are: comp-gas
12
The categories of this paper are: nucl-th
1
The categories of this paper are: cs
10
The categories of this paper are: q-bio
33
The categories of this paper are: plasm-ph
23
The categories of this paper are: solv-int
4
The categories of this paper are: cond-mat
31
The categories of this paper are: ao-sci
8
The categories of this paper are: hep-ex