Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the concurrence of superpositions of many states   In this paper we use the \textit{concurrence vector}, as a measure of
entanglement, and investigate lower and upper bounds on the concurrence of a
superposition of bipartite states as a function of the concurrence of the
superposed states. We show that the amount of entanglement quantified by the
concurrence vector is exactly the same as that quantified by
\textit{I-concurrence}, so that our results can be compared to those given in
[Phys. Rev. A {\bf 76}, 042328 (2007)]. We obtain a tighter lower bound in the
case that two superposed states are orthogonal. We also show that when the two
superposed states are not necessarily orthogonal, both lower and bounds are, in
general, tighter than the bounds given in terms of the I-concurrence. An
extension of the results to the case with more than two states in the
superpositions is also given.

5
The categories of this paper are: gr-qc
31
The categories of this paper are: ao-sci
18
The categories of this paper are: econ
23
The categories of this paper are: solv-int
22
The categories of this paper are: chao-dyn
16
The categories of this paper are: stat
28
The categories of this paper are: alg-geom
3
The categories of this paper are: physics
37
The categories of this paper are: supr-con
25
The categories of this paper are: patt-sol
33
The categories of this paper are: plasm-ph
8
The categories of this paper are: hep-ex
1
The categories of this paper are: cs
35
The categories of this paper are: mtrl-th
27
The categories of this paper are: comp-gas
9
The categories of this paper are: nlin