Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A four-dimensional Hooke's law can encompass linear elasticity and
  inertia   The question is examined, whether the formally straightforward extension of
Hooke's time-honoured stress-strain relation to the four dimensions of special
and of general relativity can make physical sense. The four-dimensional Hooke's
law is found able to account for the inertia of matter; in the flat space, slow
motion approximation the field equations for the ``displacement'' four-vector
field can encompass both linear elasticity and inertia. In this limit one just
recovers the equations of motion of the classical theory of elasticity.

13
The categories of this paper are: quant-ph
35
The categories of this paper are: mtrl-th
4
The categories of this paper are: cond-mat
12
The categories of this paper are: nucl-th
16
The categories of this paper are: stat
22
The categories of this paper are: chao-dyn
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The categories of this paper are: econ
2
The categories of this paper are: math
24
The categories of this paper are: dg-ga
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The categories of this paper are: q-alg
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The categories of this paper are: nucl-ex
32
The categories of this paper are: atom-ph
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The categories of this paper are: q-bio
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The categories of this paper are: q-fin
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The categories of this paper are: alg-geom
21
The categories of this paper are: adap-org