Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The N-steps Invasion Percolation Model   A new kind of invasion percolation is introduced in order to take into
account the inertia of the invader fluid. The inertia strength is controlled by
the number N of pores (or steps) invaded after the perimeter rupture. The new
model belongs to a different class of universality with the fractal dimensions
of the percolating clusters depending on N. A blocking phenomenon takes place
in two dimensions. It imposes an upper bound value on N. For pore sizes larger
than the critical threshold, the acceptance profile exhibits a permanent tail.

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The categories of this paper are: quant-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: ao-sci
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The categories of this paper are: mtrl-th
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The categories of this paper are: dg-ga
34
The categories of this paper are: chem-ph
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The categories of this paper are: econ
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The categories of this paper are: hep-lat
0
The categories of this paper are: hep-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: eess
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The categories of this paper are: chao-dyn
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The categories of this paper are: hep-th
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The categories of this paper are: astro-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: math-ph