Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Temporal correlation function in 3-D Turbulence   We observe oscillatory decay in the two-point, non-equal time, velocity
correlation function of homogeneous, isotropic turbulence. We found this
through a direct numerical simulation (DNS) of the three dimensional
Navier-Stokes ($3-D$ NS) equation. We give an approximate analytic theory which
explains this oscillatory behaviour. The wave-number and frequency dependent
effective viscosity turns out to be complex; the imaginary part gives rise to
the temporal oscillation. We find that, at least for the decay at short times,
data collapse occur among the inertial range velocity wave-vector modes with
the long time dynamic exponent $z=2/3$, but the time period of the temporal
oscillation is not universal.

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The categories of this paper are: math-ph
29
The categories of this paper are: funct-an
5
The categories of this paper are: gr-qc
8
The categories of this paper are: hep-ex
23
The categories of this paper are: solv-int
13
The categories of this paper are: quant-ph
27
The categories of this paper are: comp-gas
33
The categories of this paper are: plasm-ph
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The categories of this paper are: cmp-lg
25
The categories of this paper are: patt-sol
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The categories of this paper are: nucl-th
2
The categories of this paper are: math
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The categories of this paper are: alg-geom
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The categories of this paper are: q-fin
31
The categories of this paper are: ao-sci
10
The categories of this paper are: q-bio