Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Relativistic Spacetime Based on Absolute Background   Based on the consideration of naturalness and physical facts in Einstein's
theories of relativity, a nontrivial spacetime physical picture, which has a
slight difference from the standard one, is introduced by making a further
distinction on the absolute background of spacetime and the relative length or
duration of base units of spacetime. In this picture, the coordinate base units
in gravity-induced spacetime metric are defined by the standard clock and ruler
equipped by the observer, and duplicated onto the every position of the whole
universe. In contrast, the local intrinsic base units of spacetime in
gravitational field are defined by the length and duration of physical events
intervals in the same-type standard clock and ruler which are really located at
every position of the universe. In principle, the reading number of the
standard clock is counted by the undergone times of unit intervals defined
depending on a certain kind of local intrinsic events. But the size of the base
units of spacetime is essentially depicted by the length of the line segment,
which is cut from the absolute background of spacetime by the local intrinsic
events of unit interval. The effect of gravitation is just to change the length
of this segment for base spacetime units. On the basis of such a physical
picture of spacetime, in a fairly natural way we re-derive a new classical
dynamical equation which satisfies a more realistic and moderately general
principle of relativity. To further examine this physical picture including of
gravitation and spacetime, we also reinterpret the gravitational redshifts for
solar gravity tests.

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The categories of this paper are: q-alg
18
The categories of this paper are: econ
13
The categories of this paper are: quant-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: stat
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The categories of this paper are: q-fin
3
The categories of this paper are: physics
2
The categories of this paper are: math
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The categories of this paper are: plasm-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: eess
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The categories of this paper are: mtrl-th
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The categories of this paper are: alg-geom
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The categories of this paper are: supr-con
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The categories of this paper are: astro-ph
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The categories of this paper are: adap-org