Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Universal Complex Structures in Written Language   Quantitative linguistics has provided us with a number of empirical laws that
characterise the evolution of languages and competition amongst them. In terms
of language usage, one of the most influential results is Zipf's law of word
frequencies. Zipf's law appears to be universal, and may not even be unique to
human language. However, there is ongoing controversy over whether Zipf's law
is a good indicator of complexity. Here we present an alternative approach that
puts Zipf's law in the context of critical phenomena (the cornerstone of
complexity in physics) and establishes the presence of a large scale
"attraction" between successive repetitions of words. Moreover, this phenomenon
is scale-invariant and universal -- the pattern is independent of word
frequency and is observed in texts by different authors and written in
different languages. There is evidence, however, that the shape of the scaling
relation changes for words that play a key role in the text, implying the
existence of different "universality classes" in the repetition of words. These
behaviours exhibit striking parallels with complex catastrophic phenomena.

28
The categories of this paper are: alg-geom
9
The categories of this paper are: nlin
13
The categories of this paper are: quant-ph
22
The categories of this paper are: chao-dyn
11
The categories of this paper are: hep-lat
7
The categories of this paper are: hep-th
30
The categories of this paper are: q-alg
10
The categories of this paper are: q-bio
5
The categories of this paper are: gr-qc
29
The categories of this paper are: funct-an
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The categories of this paper are: comp-gas
12
The categories of this paper are: nucl-th
35
The categories of this paper are: mtrl-th
26
The categories of this paper are: bayes-an
31
The categories of this paper are: ao-sci
25
The categories of this paper are: patt-sol