Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Straightforward Derivation of the Schr{\"o}dinger Equation from
  Classical Mechanics and the Planck Postulate   According to the widely accepted notion, the Schr{\"o}dinger equation (SE) is
not derivable in principle. Contrary to this belief, we present here a
straightforward derivation of SE. It is based on only two fundamentals of
mechanics: the classical Hamilton-Jacobi equation(HJE) and the Planck postulate
about the discrete transfer of energy at micro-scales. Our approach is
drastically different from the other published derivations of SE which either
employ an ad hoc underlying assumption about the probabilistic or the
statistical nature of the micro-scale phenomena, or rely on the prior knowledge
of SE and arrive at it by introducing a new postulate - neither present in
classical mechanics nor following from experiments - with a suitable but
physically unjustifiable choice of a key arbitrary constant.

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The categories of this paper are: q-bio
33
The categories of this paper are: plasm-ph
0
The categories of this paper are: hep-ph
21
The categories of this paper are: adap-org
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The categories of this paper are: eess
5
The categories of this paper are: gr-qc
37
The categories of this paper are: supr-con
26
The categories of this paper are: bayes-an
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The categories of this paper are: cmp-lg
20
The categories of this paper are: acc-phys
30
The categories of this paper are: q-alg
12
The categories of this paper are: nucl-th
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The categories of this paper are: atom-ph
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The categories of this paper are: math
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The categories of this paper are: chem-ph
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The categories of this paper are: math-ph