Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum fidelity measures for mixed states   Applications of quantum technology often require fidelities to quantify
performance. These provide a fundamental yardstick for the comparison of two
quantum states. While this is straightforward in the case of pure states, it is
much more subtle for the more general case of mixed quantum states often found
in practice. A large number of different proposals exist. In this review, we
summarize the required properties of a quantum fidelity measure, and compare
them, to determine which properties each of the different measures has. We show
that there are large classes of measures that satisfy all the required
properties of a fidelity measure, just as there are many norms of Hilbert space
operators, and many measures of entropy. We compare these fidelities, with
detailed proofs of their properties. We also summarize briefly the applications
of these measures in teleportation, quantum memories, quantum computers,
quantum communications, and quantum phase-space simulations.

19
The categories of this paper are: eess
5
The categories of this paper are: gr-qc
10
The categories of this paper are: q-bio
7
The categories of this paper are: hep-th
3
The categories of this paper are: physics
29
The categories of this paper are: funct-an
24
The categories of this paper are: dg-ga
37
The categories of this paper are: supr-con
23
The categories of this paper are: solv-int
28
The categories of this paper are: alg-geom
30
The categories of this paper are: q-alg
20
The categories of this paper are: acc-phys
36
The categories of this paper are: cmp-lg
25
The categories of this paper are: patt-sol
34
The categories of this paper are: chem-ph
11
The categories of this paper are: hep-lat