Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Superposition principle for qubit states in spin-projection mean
  representation   The superposition principle of two qubit states is formulated as nonlinear
addition rule of mean spinprojection onto three perpendicular directions. The
explicit expression for the mean value determining the superposition state in
term of the two initial pure states of the qubit is obtained. Possibility to
check the superposition expression in experiments is discussed.

1
The categories of this paper are: cs
14
The categories of this paper are: math-ph
29
The categories of this paper are: funct-an
37
The categories of this paper are: supr-con
34
The categories of this paper are: chem-ph
23
The categories of this paper are: solv-int
9
The categories of this paper are: nlin
20
The categories of this paper are: acc-phys
24
The categories of this paper are: dg-ga
5
The categories of this paper are: gr-qc
15
The categories of this paper are: nucl-ex
0
The categories of this paper are: hep-ph
22
The categories of this paper are: chao-dyn
36
The categories of this paper are: cmp-lg
7
The categories of this paper are: hep-th
6
The categories of this paper are: astro-ph