Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The density of states of classical spin systems with continuous degrees
  of freedom   In the last years different studies have revealed the usefulness of a
microcanonical analysis of finite systems when dealing with phase transitions.
In this approach the quantities of interest are exclusively expressed as
derivatives of the entropy $S = \ln \Omega$ where $\Omega$ is the density of
states. Obviously, the density of states has to be known with very high
accuracy for this kind of analysis. Important progress has been achieved
recently in the computation of the density of states of classical systems, as
new types of algorithms have been developed. Here we extend one of these
methods, originally formulated for systems with discrete degrees of freedom, to
systems with continuous degrees of freedoms. As an application we compute the
density of states of the three-dimensional XY model and demonstrate that
critical quantities can directly be determined from the density of states of
finite systems in cases where the degrees of freedom take continuous values.

27
The categories of this paper are: comp-gas
15
The categories of this paper are: nucl-ex
3
The categories of this paper are: physics
8
The categories of this paper are: hep-ex
32
The categories of this paper are: atom-ph
6
The categories of this paper are: astro-ph
14
The categories of this paper are: math-ph
21
The categories of this paper are: adap-org
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The categories of this paper are: dg-ga
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The categories of this paper are: econ
10
The categories of this paper are: q-bio
36
The categories of this paper are: cmp-lg
20
The categories of this paper are: acc-phys
11
The categories of this paper are: hep-lat
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The categories of this paper are: supr-con
22
The categories of this paper are: chao-dyn