Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Calculation of displacement correlation tensor indicating vortical
  cooperative motion in two-dimensional colloidal liquids   As an indicator of cooperative motion in a system of Brownian particles that
models two-dimensional colloidal liquids, displacement correlation tensor is
calculated analytically and compared with numerical results. The key idea for
the analytical calculation is to relate the displacement correlation tensor,
which is a kind of four-point space-time correlation, to the Lagrangian
two-time correlation of the deformation gradient tensor. Tensorial treatment of
the statistical quantities, including the displacement correlation itself,
allows capturing the vortical structure of the cooperative motion. The
calculated displacement correlation also implies a negative longtime tail in
the velocity autocorrelation, which is a manifestation of the cage effect. Both
the longitudinal and transverse components of the displacement correlation are
found to be expressible in terms of a similarity variable, suggesting that the
cages are nested to form a self-similar structure in the space-time.

13
The categories of this paper are: quant-ph
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The categories of this paper are: eess
18
The categories of this paper are: econ
6
The categories of this paper are: astro-ph
3
The categories of this paper are: physics
23
The categories of this paper are: solv-int
37
The categories of this paper are: supr-con
31
The categories of this paper are: ao-sci
17
The categories of this paper are: q-fin
12
The categories of this paper are: nucl-th
26
The categories of this paper are: bayes-an
24
The categories of this paper are: dg-ga
33
The categories of this paper are: plasm-ph
36
The categories of this paper are: cmp-lg
11
The categories of this paper are: hep-lat
14
The categories of this paper are: math-ph