Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Review article: Linear optical quantum computing   Linear optics with photon counting is a prominent candidate for practical
quantum computing. The protocol by Knill, Laflamme, and Milburn [Nature 409, 46
(2001)] explicitly demonstrates that efficient scalable quantum computing with
single photons, linear optical elements, and projective measurements is
possible. Subsequently, several improvements on this protocol have started to
bridge the gap between theoretical scalability and practical implementation. We
review the original theory and its improvements, and we give a few examples of
experimental two-qubit gates. We discuss the use of realistic components, the
errors they induce in the computation, and how these errors can be corrected.

10
The categories of this paper are: q-bio
19
The categories of this paper are: eess
36
The categories of this paper are: cmp-lg
3
The categories of this paper are: physics
21
The categories of this paper are: adap-org
4
The categories of this paper are: cond-mat
18
The categories of this paper are: econ
26
The categories of this paper are: bayes-an
29
The categories of this paper are: funct-an
35
The categories of this paper are: mtrl-th
15
The categories of this paper are: nucl-ex
6
The categories of this paper are: astro-ph
17
The categories of this paper are: q-fin
32
The categories of this paper are: atom-ph
16
The categories of this paper are: stat
5
The categories of this paper are: gr-qc