Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A brief history of drop formation   Surface-tension-related phenomena have fascinated researchers for a long
time, and the mathematical description pioneered by Young and Laplace opened
the door to their systematic study. The time scale on which
surface-tension-driven motion takes place is usually quite short, making
experimental investigation quite demanding. Accordingly, most theoretical and
experimental work has focused on static phenomena, and in particular the
measurement of surface tension, by physicists like E\"otv\"os, Lenard, and
Bohr. Here we will review some of the work that has eventually lead to a closer
scrutiny of time-dependent flows, highly non-linear in nature. Often this
motion is self-similar in nature, such that it can in fact be mapped onto a
pseudo-stationary problem, amenable to mathematical analysis.

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The categories of this paper are: hep-lat
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The categories of this paper are: hep-ex
31
The categories of this paper are: ao-sci
36
The categories of this paper are: cmp-lg
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The categories of this paper are: nucl-th
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The categories of this paper are: stat
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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: adap-org
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The categories of this paper are: gr-qc
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The categories of this paper are: cond-mat
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The categories of this paper are: acc-phys
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The categories of this paper are: eess
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The categories of this paper are: econ
33
The categories of this paper are: plasm-ph
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The categories of this paper are: q-alg