Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Dynamics of Crystal Formation in the Greenland NorthGRIP Ice Core   The North Greenland Ice Core Project (NorthGRIP) provides paleoclimatic
information back to at about 120 kyr before present (Dahl-Jensen and others,
2002). Each year, precipitation on the ice sheet covers it with a new layer of
snow, which gradually transforms into ice crystals as the layer sinks into the
ice sheet. The size distribution of ice crystals has been measured at selected
depths in the upper 880 m of the NorthGRIP ice core (Svensson and others,
2003b), which covers a time span of 5300 years. The distributions change with
time toward a universal curve, indicating a common underlying physical process
in the formation of crystals. We identify this process as an interplay between
fragmentation of the crystals and diffusion of their grain boundaries. The
process is described by a two-parameter differential equation to which we
obtain the exact solution. The solution is in excellent agreement with the
experimentally observed distributions.

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The categories of this paper are: quant-ph
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The categories of this paper are: hep-lat
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The categories of this paper are: dg-ga
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The categories of this paper are: q-bio
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The categories of this paper are: q-alg
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The categories of this paper are: adap-org
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The categories of this paper are: patt-sol
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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: alg-geom
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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: nucl-th
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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: math