Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Extinction of Populations and the Schr\"{o}dinger Equation: Analytic
  Calculations for Abrupt Transitions   We study bifurcations in a spatially extended nonlinear system representing
population dynamics with the help of analytic calculations based on the
time-independent Schr\"{o}dinger equation for a quantum particle subjected to a
uniform gravitational field. Despite the linear character of the
Schr\"{o}dinger equation, the result we obtain helps in the understanding of
the onset of abrupt transitions leading to extinction of biological
populations. The result is expressed in terms of Airy functions and sheds light
on the behavior of bacteria in a Petri dish as well as of large animals such as
rodents moving over a landscape.

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The categories of this paper are: physics
6
The categories of this paper are: astro-ph
25
The categories of this paper are: patt-sol
18
The categories of this paper are: econ
23
The categories of this paper are: solv-int
35
The categories of this paper are: mtrl-th
27
The categories of this paper are: comp-gas
17
The categories of this paper are: q-fin
31
The categories of this paper are: ao-sci
20
The categories of this paper are: acc-phys
12
The categories of this paper are: nucl-th
33
The categories of this paper are: plasm-ph
22
The categories of this paper are: chao-dyn
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The categories of this paper are: cond-mat
11
The categories of this paper are: hep-lat
30
The categories of this paper are: q-alg