Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Self-Organized Criticality with Complex Scaling Exponents in the Train
  Model   The train model which is a variant of the Burridge-Knopoff earthquake model
is investigated for a velocity-strengthening friction law. It shows
self-organized criticality with complex scaling exponents. That is, the
probability density function of the avalanche strength is a power law times a
log-periodic function. Exact results (scaling exponent: $3/2+2\pi i/\ln 4$) are
found for a nonlocal cellular automaton which approximates the overdamped train
model. Further the influence of random static friction is discussed.

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The categories of this paper are: eess
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The categories of this paper are: atom-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: nucl-th
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The categories of this paper are: dg-ga
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The categories of this paper are: q-alg
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The categories of this paper are: q-bio
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The categories of this paper are: hep-ex
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The categories of this paper are: hep-lat
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The categories of this paper are: math-ph
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The categories of this paper are: cond-mat
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The categories of this paper are: stat
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The categories of this paper are: bayes-an
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The categories of this paper are: q-fin
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The categories of this paper are: chem-ph
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The categories of this paper are: nucl-ex