Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Theory of a spherical quantum rotors model: low--temperature regime and
  finite-size scaling   The quantum rotors model can be regarded as an effective model for the
low-temperature behavior of the quantum Heisenberg antiferromagnets. Here, we
consider a $d$-dimensional model in the spherical approximation confined to a
general geometry of the form $L^{d-d'}\times\infty^{d'}\times L_{\tau}^{z}$ (
$L$-linear space size and $L_{\tau}$-temporal size) and subjected to periodic
boundary conditions. Due to the remarkable opportunity it offers for rigorous
study of finite-size effects at arbitrary dimensionality this model may play
the same role in quantum critical phenomena as the popular Berlin-Kac spherical
model in classical critical phenomena. Close to the zero-temperature quantum
critical point, the ideas of finite-size scaling are utilized to the fullest
extent for studying the critical behavior of the model. For different
dimensions $1<d<3$ and $0\leq d'\leq d$ a detailed analysis, in terms of the
special functions of classical mathematics, for the susceptibility and the
equation of state is given. Particular attention is paid to the two-dimensional
case.

21
The categories of this paper are: adap-org
22
The categories of this paper are: chao-dyn
5
The categories of this paper are: gr-qc
28
The categories of this paper are: alg-geom
32
The categories of this paper are: atom-ph
11
The categories of this paper are: hep-lat
13
The categories of this paper are: quant-ph
16
The categories of this paper are: stat
34
The categories of this paper are: chem-ph
19
The categories of this paper are: eess
27
The categories of this paper are: comp-gas
1
The categories of this paper are: cs
7
The categories of this paper are: hep-th
6
The categories of this paper are: astro-ph
10
The categories of this paper are: q-bio
35
The categories of this paper are: mtrl-th