Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Variational Bose-Hubbard model revisited   For strongly interacting bosons in optical lattices the standard description
using Bose-Hubbard model becomes questionable. The role of excited bands
becomes important. In such a situation we compare results of simulations using
multiband Bose-Hubbard model with a recent proposition based on a time
dependent variational approach. It is shown that the latter, in its original
formulation, uses too small variational space leading often to spurious
effects. Possible expansion of variational approach is discussed.

24
The categories of this paper are: dg-ga
12
The categories of this paper are: nucl-th
30
The categories of this paper are: q-alg
36
The categories of this paper are: cmp-lg
8
The categories of this paper are: hep-ex
3
The categories of this paper are: physics
5
The categories of this paper are: gr-qc
0
The categories of this paper are: hep-ph
17
The categories of this paper are: q-fin
18
The categories of this paper are: econ
29
The categories of this paper are: funct-an
28
The categories of this paper are: alg-geom
2
The categories of this paper are: math
34
The categories of this paper are: chem-ph
14
The categories of this paper are: math-ph
25
The categories of this paper are: patt-sol