Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Amplitude and phase mode in a Bose Einstein condensate   We show that starting from the Heisenberg equations of motion for Bose
annihilation and creation operators and using an appropriate transformation, we
can split the Bogoliubov mode into a free particle mode and the amplitude mode.
We show this for both the free Bose gas as well as the Bose gas in an optical
lattice.

35
The categories of this paper are: mtrl-th
6
The categories of this paper are: astro-ph
8
The categories of this paper are: hep-ex
17
The categories of this paper are: q-fin
2
The categories of this paper are: math
12
The categories of this paper are: nucl-th
37
The categories of this paper are: supr-con
28
The categories of this paper are: alg-geom
1
The categories of this paper are: cs
25
The categories of this paper are: patt-sol
9
The categories of this paper are: nlin
33
The categories of this paper are: plasm-ph
27
The categories of this paper are: comp-gas
0
The categories of this paper are: hep-ph
13
The categories of this paper are: quant-ph
31
The categories of this paper are: ao-sci