Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Vortex-lattice formation and melting in a nonrotating Bose-Einstein
  condensate   Numerical simulations of the interference of a three-way segmented
nonrotating Bose-Einstein condensate reveal the production of a honeycomb
vortex lattice containing significant numbers of vortices and antivortices. If
confined within a trap, the lattice subsequently melts, exhibiting a rich
assortment of vortex-antivortex interactions. In contrast with nonlinear vortex
production mechanisms previously described for Bose-Einstein condensates, the
process here is shown to be primarily one of linear superposition, with initial
vortex locations approximately described by a linear theory of wave packet
interference.

2
The categories of this paper are: math
24
The categories of this paper are: dg-ga
34
The categories of this paper are: chem-ph
10
The categories of this paper are: q-bio
16
The categories of this paper are: stat
19
The categories of this paper are: eess
32
The categories of this paper are: atom-ph
30
The categories of this paper are: q-alg
25
The categories of this paper are: patt-sol
1
The categories of this paper are: cs
28
The categories of this paper are: alg-geom
23
The categories of this paper are: solv-int
6
The categories of this paper are: astro-ph
31
The categories of this paper are: ao-sci
17
The categories of this paper are: q-fin
26
The categories of this paper are: bayes-an