Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Astrophysical N-body simulations: algorithms and challenges   The subjects and key questions faced by computational astrophysics using
N-body simulations are discussed in the fields of globular star cluster
dynamics, galactic nuclei and cosmological structure formation. After a
comparison of the relevance of different N-body algorithms a new concept for a
more flexible customized special purpose computer based on a combination of
GRAPE and FPGA is proposed. It is an ideal machine for all kinds of N-body
simulations using neighbour schemes, as the Ahmad-Cohen direct N-body codes and
smoothed particle hydrodynamics for systems including gas.

32
The categories of this paper are: atom-ph
30
The categories of this paper are: q-alg
31
The categories of this paper are: ao-sci
10
The categories of this paper are: q-bio
14
The categories of this paper are: math-ph
19
The categories of this paper are: eess
24
The categories of this paper are: dg-ga
21
The categories of this paper are: adap-org
37
The categories of this paper are: supr-con
23
The categories of this paper are: solv-int
11
The categories of this paper are: hep-lat
2
The categories of this paper are: math
28
The categories of this paper are: alg-geom
15
The categories of this paper are: nucl-ex
35
The categories of this paper are: mtrl-th
13
The categories of this paper are: quant-ph