Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Bose-Einstein condensation with internal degrees of freedom in alkali
  atom gases   The Bogoliubov theory is extended to a Bose-Einstein condensation with
internal degrees of freedom, realized recently in $^{23}$Na gases where several
hyperfine states are simultaneously cooled optically. Starting with a
Hamiltonian constructed from general gauge and spin rotation symmetry
principles fundamental equations for condensate are derived. The ground state
where time reversal symmetry is broken in some case and low-lying collective
modes, e.g. spin and density wave modes, are discussed. Novel vortex as a
topological defect can be created experimentally.

11
The categories of this paper are: hep-lat
35
The categories of this paper are: mtrl-th
34
The categories of this paper are: chem-ph
25
The categories of this paper are: patt-sol
8
The categories of this paper are: hep-ex
17
The categories of this paper are: q-fin
30
The categories of this paper are: q-alg
16
The categories of this paper are: stat
2
The categories of this paper are: math
32
The categories of this paper are: atom-ph
27
The categories of this paper are: comp-gas
36
The categories of this paper are: cmp-lg
26
The categories of this paper are: bayes-an
31
The categories of this paper are: ao-sci
10
The categories of this paper are: q-bio
0
The categories of this paper are: hep-ph