Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Large Fluctuations of the Macroscopic Current in Diffusive Systems: A
  Confirmation of the Additivity Principle   Most systems, when pushed out of equilibrium, respond by building up currents
of locally-conserved observables. Understanding how microscopic dynamics
determines the averages and fluctuations of these currents is one of the main
open problems in nonequilibrium statistical physics. The additivity principle
is a theoretical proposal that allows to compute the current distribution in
many one-dimensional nonequilibrium systems. Using simulations, we confirm this
conjecture in a simple and general model of energy transport, both in the
presence of a temperature gradient and in canonical equilibrium. In particular,
we show that the current distribution displays a Gaussian regime for small
current fluctuations, as prescribed by the central limit theorem, and
non-Gaussian (exponential) tails for large current deviations, obeying in all
cases the Gallavotti-Cohen fluctuation theorem. In order to facilitate a given
current fluctuation, the system adopts a well-defined temperature profile
different from that of the steady state, and in accordance with the additivity
hypothesis predictions. System statistics during a large current fluctuation is
independent of the sign of the current, which implies that the optimal profile
(as well as higher-order profiles and spatial correlations) are invariant upon
currenst inversion. We also demonstrate that finite-time joint fluctuations of
the current and the profile are well described by the additivity functional.
These results confirm the additivity hypothesis as a general and powerful tool
to compute current distributions in many nonequilibrium systems.

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The categories of this paper are: acc-phys
10
The categories of this paper are: q-bio
15
The categories of this paper are: nucl-ex
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The categories of this paper are: patt-sol
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The categories of this paper are: stat
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The categories of this paper are: solv-int
7
The categories of this paper are: hep-th
3
The categories of this paper are: physics
31
The categories of this paper are: ao-sci
37
The categories of this paper are: supr-con
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The categories of this paper are: mtrl-th
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The categories of this paper are: chao-dyn
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The categories of this paper are: cmp-lg
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The categories of this paper are: math
8
The categories of this paper are: hep-ex
30
The categories of this paper are: q-alg